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Sample records for adhesion protein expression

  1. Connexin 43 expressed in endothelial cells modulates monocyte‑endothelial adhesion by regulating cell adhesion proteins.

    PubMed

    Yuan, Dongdong; Sun, Guoliang; Zhang, Rui; Luo, Chenfang; Ge, Mian; Luo, Gangjian; Hei, Ziqing

    2015-11-01

    Adhesion between circulating monocytes and vascular endothelial cells is a key initiator of atherosclerosis. In our previous studies, it was demonstrated that the expression of connexin (Cx)43 in monocytes modulates cell adhesion, however, the effects of the expression of Cx43 in endothelial cells remains to be elucidated. Therefore, the present study investigated the role of the expression of Cx43 in endothelial cells in the process of cell adhesion. A total of four different methods with distinct mechanisms were used to change the function and expression of Cx43 channels in human umbilical vein endothelial cells: Cx43 channel inhibitor (oleamide), enhancer (retinoic acid), overexpression of Cx43 by transfection with pcDNA‑Cx43 and knock‑down of the expression of Cx43 by small interfering RNA against Cx43. The results indicated that the upregulation of the expression of Cx43 enhanced monocyte‑endothelial adhesion and this was markedly decreased by downregulation of Cx43. This mechanism was associated with Cx43‑induced expression of vascular cell adhesion molecule‑1 and intercellular cell adhesion molecule‑1. The effects of Cx43 in endothelial cells was independent of Cx37 or Cx40. These experiments suggested that local regulation of endothelial Cx43 expression within the vasculature regulates monocyte‑endothelial adhesion, a critical event in the development of atherosclerosis and other inflammatory pathologies, with baseline adhesion set by the expression of Cx43. This balance may be crucial in controlling leukocyte involvement in inflammatory cascades.

  2. A hot water extract of Curcuma longa inhibits adhesion molecule protein expression and monocyte adhesion to TNF-α-stimulated human endothelial cells.

    PubMed

    Kawasaki, Kengo; Muroyama, Koutarou; Yamamoto, Norio; Murosaki, Shinji

    2015-01-01

    The recruitment of arterial leukocytes to endothelial cells is an important step in the progression of various inflammatory diseases. Therefore, its modulation is thought to be a prospective target for the prevention or treatment of such diseases. Adhesion molecules on endothelial cells are induced by proinflammatory cytokines, including tumor necrosis factor-α (TNF-α), and contribute to the recruitment of leukocytes. In the present study, we investigated the effect of hot water extract of Curcuma longa (WEC) on the protein expression of adhesion molecules, monocyte adhesion induced by TNF-α in human umbilical vascular endothelial cells (HUVECs). Treatment of HUVECs with WEC significantly suppressed both TNF-α-induced protein expression of adhesion molecules and monocyte adhesion. WEC also suppressed phosphorylation and degradation of nuclear factor of kappa light polypeptide gene enhancer in B-cells inhibitor, alpha (IκBα) induced by TNF-α in HUVECs, suggesting that WEC inhibits the NF-κB signaling pathway.

  3. Therapy with hydroxyurea is associated with reduced adhesion molecule gene and protein expression in sickle red cells with a concomitant reduction in adhesive properties.

    PubMed

    Gambero, Sheley; Canalli, Andreia A; Traina, Fabiola; Albuquerque, Dulcinéia M; Saad, Sara T O; Costa, Fernando F; Conran, Nicola

    2007-02-01

    Propagation of the vaso-occlusive process in sickle cell anaemia (SCA) is a complex process involving the adhesion of steady-state SCA patients red cells and reticulocytes to the vascular endothelium. The effect of hydroxyurea therapy (HUT) on the adhesive properties of sickle cells and the expression of adhesion molecule genes by erythroid cells of SCA individuals is not yet fully understood. The expressions of the CD36 gene and the VLA-4-integrin subunit genes, CD49d (alpha-subunit) and CD29 (beta-subunit), were compared in the reticulocytes of steady-state SCA patients and patients on HUT using real-time PCR. Basal adhesion of red cells from these subjects was also compared using static adhesion assays, as was surface protein expression, using flow cytometry. Basal sickle red cell adhesion to fibronectin was significantly greater than that of normal cells (P < 0.01); in contrast, HUT was associated with significantly lower levels (P < 0.01) of red cell adhesion that were similar to those of control cells; this decrease could not be justified solely by altered reticulocyte numbers in this population. Accordingly, flow cytometry demonstrated that reticulocytes from patients on HUT had significantly lower CD36 and CD49d surface expressions (P < 0.01) and, importantly, significantly lower expressions of the CD36, CD49d and CD29 genes (P < 0.05) than reticulocytes of SCA patients not on HUT. Taken together, data support the hypothesis that HUT reduces the adhesive properties of sickle cells and that this decrease appears to be mediated, at least in part, by a decrease in the gene and, consequently, surface protein expression of adhesion molecules such as VLA-4 and CD36.

  4. Plakophilin 2 Affects Cell Migration by Modulating Focal Adhesion Dynamics and Integrin Protein Expression

    PubMed Central

    Koetsier, Jennifer L.; Amargo, Evangeline V.; Todorović, Viktor; Green, Kathleen J.; Godsel, Lisa M.

    2014-01-01

    Plakophilin 2 (PKP2), a desmosome component, modulates the activity and localization of the small GTPase RhoA at sites of cell–cell contact. PKP2 regulates cortical actin rearrangement during junction formation, and its loss is accompanied by an increase in actin stress fibers. We hypothesized that PKP2 may regulate focal adhesion dynamics and cell migration. Here we show that PKP2-deficient cells bind efficiently to the extracellular matrix, but upon spreading display total cell areas ~30% smaller than control cells. Focal adhesions in PKP2-deficient cells are ~2× larger and more stable than in control cells, and vinculin displays an increased time for fluorescence recovery after photobleaching. Furthermore, β4 and β1 integrin protein and mRNA expression is elevated in PKP2-silenced cells. Normal focal adhesion phenotypes can be restored in PKP2-null cells by dampening the RhoA pathway or silencing β1 integrin. However, integrin expression levels are not restored by RhoA signaling inhibition. These data uncover a potential role for PKP2 upstream of β1 integrin and RhoA in integrating cell–cell and cell–substrate contact signaling in basal keratinocytes necessary for the morphogenesis, homeostasis, and reepithelialization of the stratified epidermis. PMID:23884246

  5. Leukocyte trafficking-associated vascular adhesion protein 1 is expressed and functionally active in atherosclerotic plaques

    PubMed Central

    Silvola, Johanna M. U.; Virtanen, Helena; Siitonen, Riikka; Hellberg, Sanna; Liljenbäck, Heidi; Metsälä, Olli; Ståhle, Mia; Saanijoki, Tiina; Käkelä, Meeri; Hakovirta, Harri; Ylä-Herttuala, Seppo; Saukko, Pekka; Jauhiainen, Matti; Veres, Tibor Z.; Jalkanen, Sirpa; Knuuti, Juhani; Saraste, Antti; Roivainen, Anne

    2016-01-01

    Given the important role of inflammation and the potential association of the leukocyte trafficking-associated adhesion molecule vascular adhesion protein 1 (VAP-1) with atherosclerosis, this study examined whether functional VAP-1 is expressed in atherosclerotic lesions and, if so, whether it could be targeted by positron emission tomography (PET). First, immunohistochemistry revealed that VAP-1 localized to endothelial cells of intra-plaque neovessels in human carotid endarterectomy samples from patients with recent ischemic symptoms. In low-density lipoprotein receptor-deficient mice expressing only apolipoprotein B100 (LDLR−/−ApoB100/100), VAP-1 was expressed on endothelial cells lining inflamed atherosclerotic lesions; normal vessel walls in aortas of C57BL/6N control mice were VAP-1-negative. Second, we discovered that the focal uptake of VAP-1 targeting sialic acid-binding immunoglobulin-like lectin 9 based PET tracer [68Ga]DOTA-Siglec-9 in atherosclerotic plaques was associated with the density of activated macrophages (r = 0.58, P = 0.022). As a final point, we found that the inhibition of VAP-1 activity with small molecule LJP1586 decreased the density of macrophages in inflamed atherosclerotic plaques in mice. Our results suggest for the first time VAP-1 as a potential imaging target for inflamed atherosclerotic plaques, and corroborate VAP-1 inhibition as a therapeutic approach in the treatment of atherosclerosis. PMID:27731409

  6. Cloning and expression of recombinant adhesive protein Mefp-1 of the blue mussel, Mytilus edulis

    DOEpatents

    Silverman, Heather G.; Roberto, Francisco F.

    2006-01-17

    The present invention comprises a Mytilus edulis cDNA sequenc having a nucleotide sequence that encodes for the Mytilus edulis foot protein-1 (Mefp-1), an example of a mollusk foot protein. Mefp-1 is an integral component of the blue mussels' adhesive protein complex, which allows the mussel to attach to objects underwater. The isolation, purification and sequencing of the Mefp-1 gene will allow researchers to produce Mefp-1 protein using genetic engineering techniques. The discovery of Mefp-1 gene sequence will also allow scientists to better understand how the blue mussel creates its waterproof adhesive protein complex.

  7. Cloning and expression of recombinant adhesive protein MEFP-2 of the blue mussel, Mytilus edulis

    DOEpatents

    Silverman, Heather G.; Roberto, Francisco F.

    2006-02-07

    The present invention includes a Mytilus edulis cDNA having a nucleotide sequence that encodes for the Mytilus edulis foot protein-2 (Mefp-2), an example of a mollusk foot protein. Mefp-2 is an integral component of the blue mussels' adhesive protein complex, which allows the mussel to attach to objects underwater. The isolation, purification and sequencing of the Mefp-2 gene will allow researchers to produce Mefp-2 protein using genetic engineering techniques. The discovery of Mefp-2 gene sequences will also allow scientists to better understand how the blue mussel creates its waterproof adhesive protein complex.

  8. Diamagnetic levitation causes changes in the morphology, cytoskeleton, and focal adhesion proteins expression in osteocytes.

    PubMed

    Qian, A R; Wang, L; Gao, X; Zhang, W; Hu, L F; Han, J; Li, J B; Di, S M; Shang, Peng

    2012-01-01

    Diamagnetic levitation technology is a novel simulated weightless technique and has recently been applied in life-science research. We have developed a superconducting magnet platform with large gradient high magnetic field (LG-HMF), which can provide three apparent gravity levels, namely, μg (diamagnetic levitation), 1g, and 2g for diamagnetic materials. In this study, the effects of LG-HMF on the activity, morphology, and cytoskeleton (actin filament, microtubules, and vimentin intermediate filaments) in osteocyte - like cell line MLO-Y4 were detected by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) methods, hematoxylin-eosin (HE) staining, and laser scanning confocal microscopy (LSCM), respectively. The changes induced by LG-HMF in distribution and expression of focal adhesion (FA) proteins, including vinculin, paxillin, and talin in MLO-Y4 were determined by LSCM and Western blotting. The results showed that LG-HMF produced by superconducting magnet had no lethal effects on MLO-Y4. Compared to control, diamagnetic levitation (μg) affected MLO-Y4 morphology, nucleus size, cytoskeleton architecture, and FA proteins distribution and expression. The study indicates that osteocytes are sensitive to altered gravity and FA proteins (vinculin, paxillin, and talin) may be involved in osteocyte mechanosensation. The diamagnetic levitation may be a novel ground-based space-gravity simulator and can be used for biological experiment at cellular level.

  9. Effects of protein tyrosine kinase inhibitors on cytokine-induced adhesion molecule expression by human umbilical vein endothelial cells.

    PubMed Central

    May, M. J.; Wheeler-Jones, C. P.; Pearson, J. D.

    1996-01-01

    1. Endothelial cells can be stimulated by the pro-inflammatory cytokines interleukin (IL)-1 alpha and tumour necrosis factor (TNF) alpha to express the leukocyte adhesion molecules E-selectin, vascular cell adhesion molecule (VCAM)-1 and intercellular adhesion molecule (ICAM)-1 but the intracellular signalling mechanisms leading to this expression are incompletely understood. We have investigated the role of protein tyrosine kinases (PTK) in adhesion molecule expression by cytokine-activated human umbilical vein endothelial cells (HUVEC) using the PTK inhibitors genistein and herbimycin A, and the protein tyrosine phosphatase (PTP) inhibitor sodium orthovanadate. 2. Maximal E-selectin expression induced by incubation of HUVEC for 4 h with IL-1 alpha (100 u ml-1) and TNF alpha (100 u ml-1) was dose-dependently inhibited by genistein and herbimycin A. Although similar effects were seen on phorbol 12-myristate, 13-acetate (PMA)-induced expression, this was not due to inhibition of protein kinase C (PKC) activity as the selective inhibitors of PKC, bisindolylmaleimide (BIM), Ro31-7549 or Ro31-8220 did not affect IL-1 alpha- or TNF alpha-induced E-selectin expression at concentrations which maximally inhibited PMA-induced expression. 3. Genistein inhibited VCAM-1 expression induced by incubation of HUVEC for 24 h with TNF alpha or IL-1 alpha whereas it did not affect ICAM-1 expression induced by 24 h incubation with either of these cytokines. Herbimycin A inhibited both VCAM-1 and ICAM-1 expression induced by TNF alpha. 4. Basal expression of E-selectin, VCAM-1 and ICAM-1 was dose-dependently enhanced by sodium orthovanadate. In contrast, vanadate differentially affected TNF alpha-induced expression of these molecules with maximal E-selectin and ICAM-1 expression being slightly enhanced and VCAM-1 expression dose-dependently reduced. 5. We also studied the effects of PTK and PTP inhibitors on adhesion of the human pre-myeloid cell line U937 to TNF alpha-stimulated HUVEC

  10. KDM4B histone demethylase and G9a regulate expression of vascular adhesion proteins in cerebral microvessels

    PubMed Central

    Choi, Ji-Young; Yoon, Sang-Sun; Kim, Sang-Eun; Ahn Jo, Sangmee

    2017-01-01

    Intercellular adhesion molecule 1 (ICAM1) mediates the adhesion and transmigration of leukocytes across the endothelium, promoting inflammation. We investigated the epigenetic mechanism regulating ICAM1 expression. The pro-inflammatory cytokine TNF-α dramatically increased ICAM1 mRNA and protein levels in human brain microvascular endothelial cells and mouse brain microvessels. Chromatin immunoprecipitation revealed that TNF-α reduced methylation of histone H3 at lysines 9 and 27 (H3K9 and H3K27), well-known residues involved in gene suppression. Inhibition of G9a and EZH2, histone methyltransferases responsible for methylation at H3K9 and H3K27, respectively as well as G9a overexpression demonstrated the involvement of G9a in TNF-α-induced ICAM1 expression and leukocyte adhesion and transmigration. A specific role for KDM4B, a histone demethylase targeting H3K9me2, in TNF-α-induced ICAM1 upregulation was validated with siRNA. Moreover, treating mice with a KDM4 inhibitor ML324 blocked TNF-α-mediated neutrophil adhesion. Similarly, TNF-α-induced VCAM1 expression was suppressed by G9a overexpression and KDM4B knockdown. Collectively, we demonstrated that modification of H3K9me2 by G9a and KDM4B regulates expression of vascular adhesion molecules, and that depletion of these proteins or KDM4B reduces inflammation-induced leukocyte extravasation. Thus, blocking ICAM1 or KDM4B could offer a novel therapeutic opportunity treating brain diseases. PMID:28327608

  11. Nicotine stimulates adhesion molecular expression via calcium influx and mitogen-activated protein kinases in human endothelial cells.

    PubMed

    Wang, Yajing; Wang, Zhaoxia; Zhou, Ying; Liu, Liming; Zhao, Yangxing; Yao, Chenjiang; Wang, Lianyun; Qiao, Zhongdong

    2006-02-01

    To evaluate the effect of nicotine on endothelium dysfunction and development of vascular diseases, we investigated the influence on adhesion molecular expression mediated by nicotine and the mechanism of this effect in human umbilical vein endothelial cells (HUVECs). The result showed that nicotine could induce surface/soluble vascular cell adhesion molecule (VCAM-1) and endothelial selectin (E-selectin) expression in a time-response decline manner and the peak appeared at 15 min. This action could be mediated by mitogen-activated protein kinase/extracellular signal regulated kinase 1/2 (MAPK/ERK1/2) and MAPK/p38 because their activation could be distinctly blocked by MAPK inhibitors, PD098059 or SB203580. Mecamylamine (non-selective nicotinic receptor inhibitor), alpha-bungarotoxin (alpha7 nicotinic receptor inhibitor) could block Ca2+ accumulation, and then, prevented the phosphorylation on ERK1/2 and p38. They also inhibited the surface/soluble VCAM-1, E-selectin production of HUVECs modulated by nicotine. Therefore, we concluded that: (i) nicotine obviously up-regulates VCAM-1 and E-selectin expression at 15 min in HUVECs, (ii) nicotine activates HUVECs triggered by the ERK1/2 and p38 phosphorylation with an involvement of intracellular calcium mobilization chiefly mediated by alpha7 nicotinic receptor, (iii) intracellular Ca2+ activates a sequential pathway from alpha7 nicotinic receptor to the phosphorylation of ERK1/2, p38. These elucidate that nicotine activates HUVECs through fast signal transduction pathway and arguments their capacity of adhesion molecular production. Further more nicotine may contribute its influence to the progression of vascular disease such as atherosclerotic lesion.

  12. Hepatocyte nuclear factor 4alpha orchestrates expression of cell adhesion proteins during the epithelial transformation of the developing liver.

    PubMed

    Battle, Michele A; Konopka, Genevieve; Parviz, Fereshteh; Gaggl, Alexandra Lerch; Yang, Chuhu; Sladek, Frances M; Duncan, Stephen A

    2006-05-30

    Epithelial formation is a central facet of organogenesis that relies on intercellular junction assembly to create functionally distinct apical and basal cell surfaces. How this process is regulated during embryonic development remains obscure. Previous studies using conditional knockout mice have shown that loss of hepatocyte nuclear factor 4alpha (HNF4alpha) blocks the epithelial transformation of the fetal liver, suggesting that HNF4alpha is a central regulator of epithelial morphogenesis. Although HNF4alpha-null hepatocytes do not express E-cadherin (also called CDH1), we show here that E-cadherin is dispensable for liver development, implying that HNF4alpha regulates additional aspects of epithelial formation. Microarray and molecular analyses reveal that HNF4alpha regulates the developmental expression of a myriad of proteins required for cell junction assembly and adhesion. Our findings define a fundamental mechanism through which generation of tissue epithelia during development is coordinated with the onset of organ function.

  13. Adhesives from modified soy protein

    DOEpatents

    Sun, Susan; Wang, Donghai; Zhong, Zhikai; Yang, Guang

    2008-08-26

    The, present invention provides useful adhesive compositions having similar adhesive properties to conventional UF and PPF resins. The compositions generally include a protein portion and modifying ingredient portion selected from the group consisting of carboxyl-containing compounds, aldehyde-containing compounds, epoxy group-containing compounds, and mixtures thereof. The composition is preferably prepared at a pH level at or near the isoelectric point of the protein. In other preferred forms, the adhesive composition includes a protein portion and a carboxyl-containing group portion.

  14. Differential Expression of Adhesion-Related Proteins and MAPK Pathways Lead to Suitable Osteoblast Differentiation of Human Mesenchymal Stem Cells Subpopulations.

    PubMed

    Leyva-Leyva, Margarita; López-Díaz, Annia; Barrera, Lourdes; Camacho-Morales, Alberto; Hernandez-Aguilar, Felipe; Carrillo-Casas, Erika M; Arriaga-Pizano, Lourdes; Calderón-Pérez, Jaime; García-Álvarez, Jorge; Orozco-Hoyuela, Gabriel; Piña-Barba, Cristina; Rojas-Martínez, Augusto; Romero-Díaz, Víktor; Lara-Arias, Jorge; Rivera-Bolaños, Nancy; López-Camarillo, César; Moncada-Saucedo, Nidia; Galván-De los Santos, Alejandra; Meza-Urzúa, Fátima; Villarreal-Gómez, Luis; Fuentes-Mera, Lizeth

    2015-11-01

    Cellular adhesion enables communication between cells and their environment. Adhesion can be achieved throughout focal adhesions and its components influence osteoblast differentiation of human mesenchymal stem cells (hMSCs). Because cell adhesion and osteoblast differentiation are closely related, this article aimed to analyze the expression profiles of adhesion-related proteins during osteoblastic differentiation of two hMSCs subpopulations (CD105(+) and CD105(-)) and propose a strategy for assembling bone grafts based on its adhesion ability. In vitro experiments of osteogenic differentiation in CD105(-) cells showed superior adhesion efficiency and 2-fold increase of α-actinin expression compared with CD105(+) cells at the maturation stage. Interestingly, levels of activated β1-integrin increased in CD105(-) cells during the process. Additionally, the CD105(-) subpopulation showed 3-fold increase of phosphorylated FAK(Y397) compared to CD105(+) cells. Results also indicate that ERK1/2 was activated during CD105(-) bone differentiation and participation of mitogen-activated protein kinase (MAPK)-p38 in CD105(+) differentiation through a focal adhesion kinase (FAK)-independent pathway. In vivo trial demonstrated that grafts containing CD105(-) showed osteocytes embedded in a mineralized matrix, promoted adequate graft integration, increased host vascular infiltration, and efficient intramembranous repairing. In contrast, grafts containing CD105(+) showed deficient endochondral ossification and fibrocartilaginous tissue. Based on the expression of α-actinin, FAKy,(397) and ERK1/2 activation, we define maturation stage as critical for bone graft assembling. By in vitro assays, CD105(-) subpopulation showed superior adhesion efficiency compared to CD105(+) cells. Considering in vitro and in vivo assays, this study suggests that integration of a scaffold with CD105(-) subpopulation at the maturation stage represents an attractive strategy for clinical use in

  15. In vivo selection for Neisseria gonorrhoeae opacity protein expression in the absence of human carcinoembryonic antigen cell adhesion molecules.

    PubMed

    Simms, Amy N; Jerse, Ann E

    2006-05-01

    The neisserial opacity (Opa) proteins are phase-variable, antigenically distinct outer membrane proteins that mediate adherence to and invasion of human cells. We previously reported that Neisseria gonorrhoeae Opa protein expression appeared to be selected for or induced during experimental murine genital tract infection. Here we further defined the kinetics of recovery of Opa variants from the lower genital tracts of female mice and investigated the basis for this initial observation. We found that the recovery of different Opa phenotypes from mice appears cyclical. Three phases of infection were defined. Following intravaginal inoculation with primarily Opa- gonococci, the majority of isolates recovered were Opa+ (early phase). A subsequent decline in the percentage of Opa+ isolates occurred in a majority of mice (middle phase) and was followed by a reemergence of Opa+ variants in mice that were infected for longer than 8 days (late phase). We showed the early phase was due to selection for preexisting Opa+ variants in the inoculum by constructing a chloramphenicol-resistant (Cm(r)) strain and following Cm(r) Opa+ populations mixed with a higher percentage of Opa- variants of the wild-type (Cm(s)) strain. Reciprocal experiments (Opa- Cm(r) gonococci spiked with Opa+ Cm(s) bacteria) were consistent with selection of Opa+ variants. Based on the absence in mice of human carcinoembryonic antigen cell adhesion molecules, the major class of Opa protein adherence receptors, we conclude the observed selection for Opa+ variants early in infection is not likely due to a specific adherence advantage and may be due to Opa-mediated evasion of innate defenses.

  16. Interleukin-6 enhances whereas tumor necrosis factor alpha and interferons inhibit integrin expression and adhesion of human mast cells to extracellular matrix proteins.

    PubMed

    Schoeler, Dagmar; Grützkau, Andreas; Henz, Beate M; Küchler, Jens; Krüger-Krasagakis, Sabine

    2003-05-01

    Integrins are expressed on mast cells and constitute an essential prerequisite for the accumulation of the cells at sites of inflammation. In order to clarify a potential contribution of inflammatory cytokines to this process, we have studied the modulation of integrin expression and adhesion of immature human mast cells (HMC-1) to extracellular matrix proteins by interleukin-6, tumor necrosis factor alpha, interferon-alpha and interferon-gamma. Corticosteroids were used for comparison. On fluorescence-activated cell sorter analysis, preincubation of cells for 48 h with different concentrations of interleukin-6 induced a significant, up to 40%, increase of alpha v alpha 5, CD49b (alpha 2), CD49e (alpha 5), CD49f (alpha 6), and CD51 (alpha v). In contrast, different concentrations of tumor necrosis factor alpha, interferon-alpha, interferon-gamma, and dexamethasone (10-8-10-10 M) inhibited expression of adhesion receptors by up to 60%, reaching significance for some but not all integrins. On semiquantitative polymerase chain reaction analysis, interleukin-6, the other cytokines, and corticosteroids significantly modulated expression of alpha1, alpha v and alpha 5 integrin chains at mRNA level. Functional significance of these findings was proven in adhesion assays using fibronectin, laminin, and vitronectin, with interleukin-6 causing significant enhancement of adhesion in all cases, tumor necrosis factor alpha and dexamethasone inducing significant reduction of adhesion to fibronectin and laminin, and interferon-gamma significantly inhibiting adhesion to fibronectin only. Specificity of interleukin-6-induced changes was demonstrated using antibodies against alpha1 and alpha 5 integrins in unstimulated and interleukin-6-prestimulated cells. These data show that interleukin-6 stimulates mast cell adhesion to extracellular matrix and thus allows for the accumulation of the cells at tissue sites by enhancing integrin expression, whereas tumor necrosis factor alpha

  17. Expression, purification and crystallization of a BH domain from the GTPase regulatory protein associated with focal adhesion kinase.

    PubMed

    Sheffield, P J; Derewenda, U; Taylor, J; Parsons, T J; Derewenda, Z S

    1999-01-01

    Signaling by small GTPases is down-regulated by GTPase activating proteins (GAPs) which enhance the rate of GTP hydrolysis. The activity of GAPs specific for Rho GTPases resides in the BH domain, many homologues of which are found in any mammalian genome. One of them was identified in the GTPase regulator associated with focal-adhesion kinase (GRAF). It shares approximately 20% sequence identity with p50RhoGAP. This GAP activates RhoA and Cdc42Hs, but not Rac. In order to dissect the molecular basis of this specificity, a 231-residue-long fragment corresponding to the BH domain of GRAF has been expressed, purified and crystallized. Trigonal crystals, of space group P3(1)21 or P3(2)21, with unit-cell dimensions a = b = 63.5, c = 90.38 A were grown from solutions of PEG 6000. Data to 2.15 A were collected from a flash-frozen sample on an R-AXIS IV imaging-plate detector mounted on a rotating anode X-ray generator.

  18. Biophysically inspired model for functionalized nanocarrier adhesion to cell surface: roles of protein expression and mechanical factors

    NASA Astrophysics Data System (ADS)

    Ramakrishnan, N.; Tourdot, Richard W.; Eckmann, David M.; Ayyaswamy, Portonovo S.; Muzykantov, Vladimir R.; Radhakrishnan, Ravi

    2016-06-01

    In order to achieve selective targeting of affinity-ligand coated nanoparticles to the target tissue, it is essential to understand the key mechanisms that govern their capture by the target cell. Next-generation pharmacokinetic (PK) models that systematically account for proteomic and mechanical factors can accelerate the design, validation and translation of targeted nanocarriers (NCs) in the clinic. Towards this objective, we have developed a computational model to delineate the roles played by target protein expression and mechanical factors of the target cell membrane in determining the avidity of functionalized NCs to live cells. Model results show quantitative agreement with in vivo experiments when specific and non-specific contributions to NC binding are taken into account. The specific contributions are accounted for through extensive simulations of multivalent receptor-ligand interactions, membrane mechanics and entropic factors such as membrane undulations and receptor translation. The computed NC avidity is strongly dependent on ligand density, receptor expression, bending mechanics of the target cell membrane, as well as entropic factors associated with the membrane and the receptor motion. Our computational model can predict the in vivo targeting levels of the intracellular adhesion molecule-1 (ICAM1)-coated NCs targeted to the lung, heart, kidney, liver and spleen of mouse, when the contributions due to endothelial capture are accounted for. The effect of other cells (such as monocytes, etc.) do not improve the model predictions at steady state. We demonstrate the predictive utility of our model by predicting partitioning coefficients of functionalized NCs in mice and human tissues and report the statistical accuracy of our model predictions under different scenarios.

  19. Biophysically inspired model for functionalized nanocarrier adhesion to cell surface: roles of protein expression and mechanical factors

    PubMed Central

    Ramakrishnan, N.; Tourdot, Richard W.; Eckmann, David M.; Ayyaswamy, Portonovo S.; Muzykantov, Vladimir R.; Radhakrishnan, Ravi

    2016-01-01

    In order to achieve selective targeting of affinity–ligand coated nanoparticles to the target tissue, it is essential to understand the key mechanisms that govern their capture by the target cell. Next-generation pharmacokinetic (PK) models that systematically account for proteomic and mechanical factors can accelerate the design, validation and translation of targeted nanocarriers (NCs) in the clinic. Towards this objective, we have developed a computational model to delineate the roles played by target protein expression and mechanical factors of the target cell membrane in determining the avidity of functionalized NCs to live cells. Model results show quantitative agreement with in vivo experiments when specific and non-specific contributions to NC binding are taken into account. The specific contributions are accounted for through extensive simulations of multivalent receptor–ligand interactions, membrane mechanics and entropic factors such as membrane undulations and receptor translation. The computed NC avidity is strongly dependent on ligand density, receptor expression, bending mechanics of the target cell membrane, as well as entropic factors associated with the membrane and the receptor motion. Our computational model can predict the in vivo targeting levels of the intracellular adhesion molecule-1 (ICAM1)-coated NCs targeted to the lung, heart, kidney, liver and spleen of mouse, when the contributions due to endothelial capture are accounted for. The effect of other cells (such as monocytes, etc.) do not improve the model predictions at steady state. We demonstrate the predictive utility of our model by predicting partitioning coefficients of functionalized NCs in mice and human tissues and report the statistical accuracy of our model predictions under different scenarios. PMID:27429783

  20. Expression, purification, crystallization and preliminary X-ray analysis of the olfactomedin domain from the sea urchin cell-adhesion protein amassin

    SciTech Connect

    Hillier, Brian J.; Sundaresan, Vidyasankar; Stout, C. David; Vacquier, Victor D.

    2006-01-01

    The olfactomedin (OLF) domain from the sea urchin cell-adhesion protein amassin has been crystallized. A native data set extending to 2.7 Å has been collected using an in-house X-ray source. A family of animal proteins is emerging which contain a conserved protein motif known as an olfactomedin (OLF) domain. Novel extracellular protein–protein interactions occur through this domain. The OLF-family member amassin, from the sea urchin Strongylocentrotus purpuratus, has previously been identified to mediate a rapid cell-adhesion event resulting in a large aggregation of coelomocytes, the circulating immune cells. In this work, heterologous expression and purification of the OLF domain from amassin was carried out and initial crystallization trials were performed. A native data set has been collected, extending to 2.7 Å under preliminary cryoconditions, using an in-house generator. This work leads the way to the determination of the first structure of an OLF domain.

  1. Modulation of endogenous Cysteine Protease Inhibitor (ICP) 1 expression in Entamoeba histolytica affects amoebic adhesion to Extracellular Matrix proteins.

    PubMed

    Lee, Young Ah; Saito-Nakano, Yumiko; Kim, Kyeong Ah; Min, Arim; Nozaki, Tomoyoshi; Shin, Myeong Heon

    2015-02-01

    Entamoeba histolytica is an enteric tissue-invading protozoan parasite that causes amoebic colitis and occasionally liver abscess in humans. During tissue invasion, amoebic adhesion to host components is an important event for host cell death leading to successful invasion and infection. Among amoebic virulence factors, Gal/GalNAc lectin is known to be major adhesion factor to host cells. In this study, we investigated the role of amoebic secreted CP (Cysteine Proteases) in amoebic adhesion to extracellular matrix (ECM) protein using CP inhibitor and E. histolytica strains in which the endogenous inhibitor of cysteine protease (ICP) 1 gene was overexpressed (ICP1(+)) or repressed by antisense small RNA-mediated gene silencing (ICP1(-)). We found that pretreatment of wild-type amoebae with CP inhibitor E64, or thiol-group modifiers such as diamide and N-Ethylmaleimide resulted in a significant decrease in adhesion to laminin and collagen ECM proteins. Furthermore, ICP1(+) strain, with a reduction of secreted CP activity, exhibited reduced ability by 40% to adhere to laminin. In contrast, ICP1(-) strain, with a 1.9-fold increase of secreted CP activity, showed a two-fold increase in amoebic adherence to laminin compared to the control strain. In addition, total amount of secreted CP5 was decreased in ICP1(+) amoeba. Conversely, total amount of secreted CP1 and mature-form CP5 were increased in ICP1(-) amoeba. We also found that ICP1 was secreted into extracellular milieu. These results suggest that secreted CP activity by E. histolytica may be an important factor affecting adhesion to host proteins, and regulation of CP secretion by ICP plays a major role in pathogenesis. This study provides insight into the CP-mediated tissue pathogenesis in amoeba-invaded lesions during human amoebiasis.

  2. The 18-kDa Translocator Protein Inhibits Vascular Cell Adhesion Molecule-1 Expression via Inhibition of Mitochondrial Reactive Oxygen Species

    PubMed Central

    Joo, Hee Kyoung; Lee, Yu Ran; Kang, Gun; Choi, Sunga; Kim, Cuk-Seong; Ryoo, Sungwoo; Park, Jin Bong; Jeon, Byeong Hwa

    2015-01-01

    Translocator protein 18 kDa (TSPO) is a mitochondrial outer membrane protein and is abundantly expressed in a variety of organ and tissues. To date, the functional role of TSPO on vascular endothelial cell activation has yet to be fully elucidated. In the present study, the phorbol 12-myristate 13-acetate (PMA, 250 nM), an activator of protein kinase C (PKC), was used to induce vascular endothelial activation. Adenoviral TSPO overexpression (10–100 MOI) inhibited PMA-induced vascular cell adhesion molecule-1 (VCAM-1) and intracellular cell adhesion molecule-1 (ICAM-1) expression in a dose dependent manner. PMA-induced VCAM-1 expressions were inhibited by Mito-TEMPO (0.1–0.5 μM), a specific mitochondrial antioxidants, and cyclosporin A (1–5 μM), a mitochondrial permeability transition pore inhibitor, implying on an important role of mitochondrial reactive oxygen species (ROS) on the endothelial activation. Moreover, adenoviral TSPO overexpression inhibited mitochondrial ROS production and manganese superoxide dismutase expression. On contrasts, gene silencing of TSPO with siRNA increased PMA-induced VCAM-1 expression and mitochondrial ROS production. Midazolam (1–50 μM), TSPO ligands, inhibited PMA-induced VCAM-1 and mitochondrial ROS production in endothelial cells. These results suggest that mitochondrial TSPO can inhibit PMA-induced endothelial inflammation via suppression of VCAM-1 and mitochondrial ROS production in endothelial cells. PMID:26608360

  3. Inhibition of Adhesion Molecule Gene Expression and Cell Adhesion by the Metabolic Regulator PGC-1α.

    PubMed

    Minsky, Neri; Roeder, Robert G

    2016-01-01

    Cell adhesion plays an important role in determining cell shape and function in a variety of physiological and pathophysiological conditions. While links between metabolism and cell adhesion were previously suggested, the exact context and molecular details of such a cross-talk remain incompletely understood. Here we show that PGC-1α, a pivotal transcriptional co-activator of metabolic gene expression, acts to inhibit expression of cell adhesion genes. Using cell lines, primary cells and mice, we show that both endogenous and exogenous PGC-1α down-regulate expression of a variety of cell adhesion molecules. Furthermore, results obtained using mRNA stability measurements as well as intronic RNA expression are consistent with a transcriptional effect of PGC-1α on cell adhesion gene expression. Interestingly, the L2/L3 motifs of PGC-1α, necessary for nuclear hormone receptor activation, are only partly required for inhibition of several cell adhesion genes by PGC-1α. Finally, PGC-1α is able to modulate adhesion of primary fibroblasts and hepatic stellate cells to extracellular matrix proteins. Our results delineate a cross talk between a central pathway controlling metabolic regulation and cell adhesion, and identify PGC-1α as a molecular link between these two major cellular networks.

  4. Inhibition of Adhesion Molecule Gene Expression and Cell Adhesion by the Metabolic Regulator PGC-1α

    PubMed Central

    Minsky, Neri; Roeder, Robert G.

    2016-01-01

    Cell adhesion plays an important role in determining cell shape and function in a variety of physiological and pathophysiological conditions. While links between metabolism and cell adhesion were previously suggested, the exact context and molecular details of such a cross-talk remain incompletely understood. Here we show that PGC-1α, a pivotal transcriptional co-activator of metabolic gene expression, acts to inhibit expression of cell adhesion genes. Using cell lines, primary cells and mice, we show that both endogenous and exogenous PGC-1α down-regulate expression of a variety of cell adhesion molecules. Furthermore, results obtained using mRNA stability measurements as well as intronic RNA expression are consistent with a transcriptional effect of PGC-1α on cell adhesion gene expression. Interestingly, the L2/L3 motifs of PGC-1α, necessary for nuclear hormone receptor activation, are only partly required for inhibition of several cell adhesion genes by PGC-1α. Finally, PGC-1α is able to modulate adhesion of primary fibroblasts and hepatic stellate cells to extracellular matrix proteins. Our results delineate a cross talk between a central pathway controlling metabolic regulation and cell adhesion, and identify PGC-1α as a molecular link between these two major cellular networks. PMID:27984584

  5. Effects of the knockdown of death-associated protein 3 expression on cell adhesion, growth and migration in breast cancer cells.

    PubMed

    Wazir, Umar; Sanders, Andrew J; Wazir, Ahmad M A; Ye, Lin; Jiang, Wen G; Ster, Irina C; Sharma, Anup K; Mokbel, Kefah

    2015-05-01

    The death-associated protein 3 (DAP3) is a highly conserved phosphoprotein involved in the regulation of autophagy. A previous clinical study by our group suggested an association between low DAP3 expression and clinicopathological parameters of human breast cancer. In the present study, we intended to determine the role of DAP3 in cancer cell behaviour in the context of human breast cancer. We developed knockdown sub-lines of MCF7 and MDA-MB-231, and performed growth, adhesion, invasion assays and electric cell-substrate impedance sensing (ECIS) studies of post-wound migration of the cells. In addition, we studied the mRNA expression of caspase 8 and 9, death ligand signal enhancer (DELE), IFN-β promoter stimulator 1 (IPS1), cyclin D1 and p21 in the control and knockdown sub-lines. The knockdown sub-lines of MCF7 and MDA-MB-231 had significantly increased adhesion and decreased growth when compared to the controls. Furthermore, invasion and migration were significantly increased in the MDA-MB-231DAP3kd cells vs. the controls. The expression of caspase 9 and IPS1, known components of the apoptosis pathway, were significantly reduced in the MCF7DAP3kd cells (p=0.05 and p=0.003, respectively). We conclude that DAP3 silencing contributes to breast carcinogenesis by increasing cell adhesion, migration and invasion. It is possible that this may be due to the activity of focal adhesion kinase further downstream of the anoikis pathway. Further research in this direction would be beneficial in increasing our understanding of the mechanisms underlying human breast cancer.

  6. Adhesion family of G protein-coupled receptors and cancer.

    PubMed

    Lin, Hsi-Hsien

    2012-01-01

    The adhesion-class G protein-coupled receptors (adhesion-GPCRs) constitute the second largest GPCR sub-family in humans. Adhesion-GPCRs are defined by the chimeric structure of an unusually large extracellular cell-adhesion domain and a GPCR-like seven-pass transmembrane domain. Adhesion-GPCRs are hence expected to display both cellular adhesion and signaling functions in many biological systems. Adhesion-GPCRs are normally expressed in the central nervous, immune, and reproductive systems in a cell type- or tissue-restricted fashion. However, aberrant expression of distinct adhesion-GPCR molecules has been identified in various human cancers with some of the receptors closely associated with cancer development. Tumor-associated adhesion-GPCRs are thought to involve in tumorigenesis by affecting the growth of tumor cells, angiogenesis, tumor cell migration, invasion and metastasis either positively or negatively. Furthermore, some adhesion-GPCRs are considered potential biomarkers for specific types of cancers. In this review article, the expressional characteristics and functional role of cancer-associated adhesion-GPCRs are discussed in depth.

  7. The adhesive properties of coacervated recombinant hybrid mussel adhesive proteins.

    PubMed

    Lim, Seonghye; Choi, Yoo Seong; Kang, Dong Gyun; Song, Young Hoon; Cha, Hyung Joon

    2010-05-01

    Marine mussels attach to substrates using adhesive proteins. It has been suggested that complex coacervation (liquid-liquid phase separation via concentration) might be involved in the highly condensed and non-water dispersed adhesion process of mussel adhesive proteins (MAPs). However, as purified natural MAPs are difficult to obtain, it has not been possible to experimentally validate the coacervation model. In the present work, we demonstrate complex coacervation in a system including recombinant MAPs and hyaluronic acid (HA). Our recombinant hybrid MAPs, fp-151 and fp-131, can be produced in large quantities, and are readily purified. We observed successful complex coacervation using cationic fp-151 or fp-131, and an anionic HA partner. Importantly, we found that highly condensed complex coacervates significantly increased the bulk adhesive strength of MAPs in both dry and wet environments. In addition, oil droplets were successfully engulfed using a MAP-based interfacial coacervation process, to form microencapsulated particles. Collectively, our results indicate that a complex coacervation system based on MAPs shows superior adhesive properties, combined with additional valuable features including liquid/liquid phase separation and appropriate viscoelasticity. Our microencapsulation system could be useful in the development of new adhesive biomaterials, including self-adhesive microencapsulated drug carriers, for use in biotechnological and biomedical applications.

  8. Tenomodulin Expression in the Periodontal Ligament Enhances Cellular Adhesion

    PubMed Central

    Komiyama, Yuske; Ohba, Shinsuke; Shimohata, Nobuyuki; Nakajima, Keiji; Hojo, Hironori; Yano, Fumiko; Takato, Tsuyoshi; Docheva, Denitsa; Shukunami, Chisa; Hiraki, Yuji; Chung, Ung-il

    2013-01-01

    Tenomodulin (Tnmd) is a type II transmembrane protein characteristically expressed in dense connective tissues such as tendons and ligaments. Its expression in the periodontal ligament (PDL) has also been demonstrated, though the timing and function remain unclear. We investigated the expression of Tnmd during murine tooth eruption and explored its biological functions in vitro. Tnmd expression was related to the time of eruption when occlusal force was transferred to the teeth and surrounding tissues. Tnmd overexpression enhanced cell adhesion in NIH3T3 and human PDL cells. In addition, Tnmd-knockout fibroblasts showed decreased cell adhesion. In the extracellular portions of Tnmd, the BRICHOS domain or CS region was found to be responsible for Tnmd-mediated enhancement of cell adhesion. These results suggest that Tnmd acts on the maturation or maintenance of the PDL by positively regulating cell adhesion via its BRICHOS domain. PMID:23593173

  9. Differential regulation of extracellular matrix protein expression in carcinoma-associated fibroblasts by TGF-β1 regulates cancer cell spreading but not adhesion

    PubMed Central

    Van Bockstal, Mieke; Lambein, Kathleen; Van Gele, Mireille; De Vlieghere, Elly; Limame, Ridha; Braems, Geert; Van den Broecke, Rudy; Cocquyt, Veronique; Denys, Hannelore; Bracke, Marc; Libbrecht, Louis; De Wever, Olivier

    2014-01-01

    Cancer progression is characterized by a complex reciprocity between neoplastic epithelium and adjacent stromal cells. In ductal carcinoma in situ (DCIS) of the breast, both reduced stromal decorin expression and myxoid stroma are correlated with increased recurrence risk. In this study, we aimed to investigate paracrine regulation of expression of decorin and related extracellular matrix (ECM) proteins in cancer-associated fibroblasts (CAFs). Transforming growth factor-β1 (TGF-β1) was identified as a competent ECM modulator, as it reduced decorin and strongly enhanced versican, biglycan and type I collagen expression. Similar but less pronounced effects were observed when fibroblasts were treated with basic fibroblast growth factor (bFGF). Despite this concerted ECM modulation, TGF-β1 and bFGF differentially regulated alpha-smooth muscle actin (α-SMA) expression, which is often proposed as a CAF-marker. Cancer cell-derived secretomes induced versican and biglycan expression in fibroblasts. Immunohistochemistry on twenty DCIS specimens showed a trend toward periductal versican overexpression in DCIS with myxoid stroma. Cancer cell adhesion was inhibited by decorin, but not by CAF-derived matrices. Cancer cells presented significantly enhanced spreading when seeded on matrices derived from TGF-β1-treated CAF. Altogether these data indicate that preinvasive cancerous lesions might modulate the composition of surrounding stroma through TGF-β1 release to obtain an invasion-permissive microenvironment. PMID:25593993

  10. TM9/Phg1 and SadA proteins control surface expression and stability of SibA adhesion molecules in Dictyostelium.

    PubMed

    Froquet, Romain; le Coadic, Marion; Perrin, Jackie; Cherix, Nathalie; Cornillon, Sophie; Cosson, Pierre

    2012-02-01

    TM9 proteins form a family of conserved proteins with nine transmembrane domains essential for cellular adhesion in many biological systems, but their exact role in this process remains unknown. In this study, we found that genetic inactivation of the TM9 protein Phg1A dramatically decreases the surface levels of the SibA adhesion molecule in Dictyostelium amoebae. This is due to a decrease in sibA mRNA levels, in SibA protein stability, and in SibA targeting to the cell surface. A similar phenotype was observed in cells devoid of SadA, a protein that does not belong to the TM9 family but also exhibits nine transmembrane domains and is essential for cellular adhesion. A contact site A (csA)-SibA chimeric protein comprising only the transmembrane and cytosolic domains of SibA and the extracellular domain of the Dictyostelium surface protein csA also showed reduced stability and relocalization to endocytic compartments in phg1A knockout cells. These results indicate that TM9 proteins participate in cell adhesion by controlling the levels of adhesion proteins present at the cell surface.

  11. Heterologous expression of newly identified galectin-8 from sea urchin embryos produces recombinant protein with lactose binding specificity and anti-adhesive activity

    PubMed Central

    Karakostis, Kostantinos; Costa, Caterina; Zito, Francesca; Matranga, Valeria

    2015-01-01

    Galectin family members specifically bind beta-galactoside derivatives and are involved in different cellular events, including cell communication, signalling, apoptosis, and immune responses. Here, we report a tandem-repeat type galectin from the Paracentrotus lividus sea urchin embryo, referred to as Pl-GAL-8. The 933nt sequence encodes a protein of 34.73 kDa, containing the conserved HFNPRF and WGxExR motifs in the two highly similar carbohydrate-recognition domains (CRD). The three-dimensional protein structure model of the N-CRD confirms the high evolutionary conservation of carbohydrate binding sites. The temporal gene expression is regulated during development and transcripts localize at the tip of the archenteron at gastrula stage, in a subset of the secondary mesenchyme cells that differentiate into blastocoelar (immune) cells. Functional studies using a recombinant Pl-GAL-8 expressed in bacteria demonstrate its hemo-agglutinating activity on human red blood cells through the binding to lactose, as well as its ability in inhibiting the adhesion of human Hep-G2 cells to the substrate. The recent implications in autoimmune diseases and inflammatory disorders make Gal-8 an attractive candidate for therapeutic purposes. Our results offer a solid basis for addressing the use of the new Pl-GAL-8 in functional and applicative studies, respectively in the developmental and biomedical fields. PMID:26640155

  12. Wood adhesives containing proteins and carbohydrates

    Technology Transfer Automated Retrieval System (TEKTRAN)

    In recent years there has been resurgent interest in using biopolymers as sustainable and environmentally friendly ingredients in wood adhesive formulations. Among them, proteins and carbohydrates are the most commonly used. In this chapter, an overview is given of protein-based and carbohydrate-...

  13. Molecular mechanics of mussel adhesion proteins

    NASA Astrophysics Data System (ADS)

    Qin, Zhao; Buehler, Markus J.

    2014-01-01

    Mussel foot protein (mfp), a natural glue produced by marine mussel, is an intriguing material because of its superior ability for adhesion in various environments. For example, a very small amount of this material is sufficient to affix a mussel to a substrate in water, providing structural support under extreme forces caused by the dynamic effects of waves. Towards a more complete understanding of its strength and underwater workability, it is necessary to understand the microscropic mechanisms by which the protein structure interacts with various substrates. However, none of the mussel proteins' structure is known, preventing us from directly using atomistic modeling to probe their structural and mechanical properties. Here we use an advanced molecular sampling technique to identify the molecular structures of two mussel foot proteins (mfp-3 and mfp-5) and use those structures to study their mechanics of adhesion, which is then incorporated into a continuum model. We calculate the adhesion energy of the mussel foot protein on a silica substrate, compute the adhesion strength based on results obtained from molecular modeling, and compare with experimental data. Our results show good agreement with experimental measurements, which validates the multiscale model. We find that the molecular structure of the folded mussel foot protein (ultimately defined by its genetic sequence) favors strong adhesion to substrates, where L-3,4-dihydroxyphenylalanine (or DOPA) protein subunits work in a cooperative manner to enhance adhesion. Our experimental data suggests a peak attachment force of 0.4±0.1 N, which compares favorably with the prediction from the multiscale model of Fc=0.21-0.33 N. The principles learnt from those results could guide the fabrication of new interfacial materials (e.g. composites) to integrate organic with inorganic surfaces in an effective manner.

  14. Dancing to Another Tune—Adhesive Moonlighting Proteins in Bacteria

    PubMed Central

    Kainulainen, Veera; Korhonen, Timo K.

    2014-01-01

    Biological moonlighting refers to proteins which express more than one function. Moonlighting proteins occur in pathogenic and commensal as well as in Gram-positive and Gram-negative bacteria. The canonical functions of moonlighting proteins are in essential cellular processes, i.e., glycolysis, protein synthesis, chaperone activity, and nucleic acid stability, and their moonlighting functions include binding to host epithelial and phagocytic cells, subepithelia, cytoskeleton as well as to mucins and circulating proteins of the immune and hemostatic systems. Sequences of the moonlighting proteins do not contain known motifs for surface export or anchoring, and it has remained open whether bacterial moonlighting proteins are actively secreted to the cell wall or whether they are released from traumatized cells and then rebind onto the bacteria. In lactobacilli, ionic interactions with lipoteichoic acids and with cell division sites are important for surface localization of the proteins. Moonlighting proteins represent an abundant class of bacterial adhesins that are part of bacterial interactions with the environment and in responses to environmental changes. Multifunctionality in bacterial surface proteins appears common: the canonical adhesion proteins fimbriae express also nonadhesive functions, whereas the mobility organelles flagella as well as surface proteases express adhesive functions. PMID:24833341

  15. Purification of adhesive proteins from mussels.

    PubMed

    Pardo, J; Gutierrez, E; Sáez, C; Brito, M; Burzio, L O

    1990-11-01

    The adhesive polyphenolic proteins from the mussels Mytilus chilensis and Choromytilus chorus have been purified based on their solubility in dilute perchloric acid and on differential precipitation with acetone containing about 0.3 N HCl. The specific activity of the proteins obtained was 0.16 mg of 3,4-dihydroxyphenylalanine per milligram of protein, or higher. The proteins have an apparent molecular weight of about 100,000 and they contain a high proportion of 3,4-dihydroxyphenylalanine, lysine, and proline.

  16. The MRL proteins: adapting cell adhesion, migration and growth.

    PubMed

    Coló, Georgina P; Lafuente, Esther M; Teixidó, Joaquin

    2012-01-01

    MIG-10, RIAM and Lamellipodin (Lpd) are the founding members of the MRL family of multi-adaptor molecules. These proteins have common domain structures but display distinct functions in cell migration and adhesion, signaling, and in cell growth. The binding of RIAM with active Rap1 and with talin provides these MRL molecules with important regulatory roles on integrin-mediated cell adhesion and migration. Furthermore, RIAM and Lpd can regulate actin dynamics through their binding to actin regulatory Ena/VASP proteins. Recent data generated with the Drosophila MRL ortholog called Pico and with RIAM in melanoma cells indicate that these proteins can also regulate cell growth. As MRL proteins represent a relatively new family, many questions on their structure-function relationships remain unanswered, including regulation of their expression, post-translational modifications, new interactions, involvement in signaling and their knockout mice phenotype.

  17. Soy and cottonseed protein blends as wood adhesives

    Technology Transfer Automated Retrieval System (TEKTRAN)

    As an environmentally friendlier alternative to adhesives from petroleum feedstock, soy proteins are currently being formulated as wood adhesives. Cottonseed proteins have also been found to provide good adhesive properties. In at least some cases, cottonseed proteins appear to form greater shear ...

  18. ZF21 protein regulates cell adhesion and motility.

    PubMed

    Nagano, Makoto; Hoshino, Daisuke; Sakamoto, Takeharu; Kawasaki, Noritaka; Koshikawa, Naohiko; Seiki, Motoharu

    2010-07-02

    Cell migration on an extracellular matrix (ECM) requires continuous formation and turnover of focal adhesions (FAs) along the direction of cell movement. However, our knowledge of the components of FAs and the mechanism of their regulation remains limited. Here, we identify ZF21, a member of a protein family characterized by the presence of a phosphatidylinositol 3-phosphate-binding FYVE domain, to be a new regulator of FAs and cell movement. Knockdown of ZF21 expression in cells increased the number of FAs and suppressed cell migration. Knockdown of ZF21 expression also led to a significant delay in FA disassembly following induction of synchronous disassembly of FAs by nocodazole treatment. ZF21 bound to focal adhesion kinase, localized to FAs, and was necessary for dephosphorylation of FAK at Tyr(397), which is important for disassembly of FAs. Thus, ZF21 represents a new component of FAs, mediates disassembly of FAs, and thereby regulates cell motility.

  19. Tocotrienol is the most effective vitamin E for reducing endothelial expression of adhesion molecules and adhesion to monocytes.

    PubMed

    Theriault, Andre; Chao, Jun-Tzo; Gapor, Abdul; Chao, Jun Tzo; Gapor, Abeli

    2002-01-01

    Alpha-tocopherol and its esterified derivatives have been shown to be effective in reducing monocytic-endothelial cell adhesion. However, the effect of alpha-tocotrienol (alpha-T3) has not been characterized. In the present study, using human umbilical vein endothelial cells (HUVEC) as the model system, we examined the relative inhibitory effects of alpha-T3 and other vitamin E derivatives on cell surface adhesion molecule expression under TNF-alpha stimulation. Using enzyme-linked immunosorbent assay, we demonstrated that alpha-T3 markedly inhibited the surface expression of vascular cell adhesion molecule-1 in TNF-alpha activated HUVEC in a dose- and time-dependent manner. The optimal inhibition was observed at 25 micromol/l alpha-T3 within 24 h (77+/-5%) without cytotoxicity. In addition, the surface expression of intercellular adhesion molecule-1 and E-selectin were also reduced by 40+/-7 and 42+/-5%, respectively. In order to further evaluate the effects of alpha-T3 on the vascular endothelium, we investigated the ability of monocytes to adhere to endothelial cells. Interestingly, a 63+/-3% decrease in monocytic cell adherence was observed. Compared to alpha-tocopherol and alpha-tocopheryl succinate, alpha-T3 displayed a more profound inhibitory effect on adhesion molecule expression and monocytic cell adherence. This inhibitory action by alpha-T3 on TNF-alpha-induced monocyte adhesion was shown to be NF-kappaB dependent and was interestingly reversed with co-incubation with farnesol and geranylgeraniol, suggesting a role for prenylated proteins in the regulation of adhesion molecule expression. In summary, the above results suggest that alpha-T3 is a potent and effective agent in the reduction of cellular adhesion molecule expression and monocytic cell adherence.

  20. Protein conformation as a regulator of cell-matrix adhesion.

    PubMed

    Hytönen, Vesa P; Wehrle-Haller, Bernhard

    2014-04-14

    The dynamic regulation of cell-matrix adhesion is essential for tissue homeostasis and architecture, and thus numerous pathologies are linked to altered cell-extracellular matrix (ECM) interaction and ECM scaffold. The molecular machinery involved in cell-matrix adhesion is complex and involves both sensory and matrix-remodelling functions. In this review, we focus on how protein conformation controls the organization and dynamics of cell-matrix adhesion. The conformational changes in various adhesion machinery components are described, including examples from ECM as well as cytoplasmic proteins. The discussed mechanisms involved in the regulation of protein conformation include mechanical stress, post-translational modifications and allosteric ligand-binding. We emphasize the potential role of intrinsically disordered protein regions in these processes and discuss the role of protein networks and co-operative protein interactions in the formation and consolidation of cell-matrix adhesion and extracellular scaffolds.

  1. Improved adhesive properties of recombinant bifidobacteria expressing the Bifidobacterium bifidum-specific lipoprotein BopA

    PubMed Central

    2012-01-01

    Background Bifidobacteria belong to one of the predominant bacterial groups in the intestinal microbiota of infants and adults. Several beneficial effects on the health status of their human hosts have been demonstrated making bifidobacteria interesting candidates for probiotic applications. Adhesion of probiotics to the intestinal epithelium is discussed as a prerequisite for colonisation of and persistence in the gastrointestinal tract. Results In the present study, 15 different strains of bifidobacteria were tested for adhesion. B. bifidum was identified as the species showing highest adhesion to all tested intestinal epithelial cell (IEC) lines. Adhesion of B. bifidum S17 to IECs was strongly reduced after treatment of bacteria with pronase. These results strongly indicate that a proteinaceous cell surface component mediates adhesion of B. bifidum S17 to IECs. In silico analysis of the currently accessible Bifidobacterium genomes identified bopA encoding a lipoprotein as a B. bifidum-specific gene previously shown to function as an adhesin of B. bifidum MIMBb75. The in silico results were confirmed by Southern Blot analysis. Furthermore, Northern Blot analysis demonstrated that bopA is expressed in all B. bifidum strains tested under conditions used to cultivate bacteria for adhesion assays. The BopA gene was successfully expressed in E. coli and purified by Ni-NTA affinity chromatography as a C-terminal His6-fusion. Purified BopA had an inhibitory effect on adhesion of B. bifidum S17 to IECs. Moreover, bopA was successfully expressed in B. bifidum S17 and B. longum/infantis E18. Strains overexpressing bopA showed enhanced adhesion to IECs, clearly demonstrating a role of BopA in adhesion of B. bifidum strains. Conclusions BopA was identified as a B. bifidum-specific protein involved in adhesion to IECs. Bifidobacterium strains expressing bopA show enhanced adhesion. Our results represent the first report on recombinant bifidobacteria with improved adhesive

  2. Mussel adhesion is dictated by time-regulated secretion and molecular conformation of mussel adhesive proteins.

    PubMed

    Petrone, Luigi; Kumar, Akshita; Sutanto, Clarinda N; Patil, Navinkumar J; Kannan, Srinivasaraghavan; Palaniappan, Alagappan; Amini, Shahrouz; Zappone, Bruno; Verma, Chandra; Miserez, Ali

    2015-10-28

    Interfacial water constitutes a formidable barrier to strong surface bonding, hampering the development of water-resistant synthetic adhesives. Notwithstanding this obstacle, the Asian green mussel Perna viridis attaches firmly to underwater surfaces via a proteinaceous secretion (byssus). Extending beyond the currently known design principles of mussel adhesion, here we elucidate the precise time-regulated secretion of P. viridis mussel adhesive proteins. The vanguard 3,4-dihydroxy-L-phenylalanine (Dopa)-rich protein Pvfp-5 acts as an adhesive primer, overcoming repulsive hydration forces by displacing surface-bound water and generating strong surface adhesion. Using homology modelling and molecular dynamics simulations, we find that all mussel adhesive proteins are largely unordered, with Pvfp-5 adopting a disordered structure and elongated conformation whereby all Dopa residues reside on the protein surface. Time-regulated secretion and structural disorder of mussel adhesive proteins appear essential for optimizing extended nonspecific surface interactions and byssus' assembly. Our findings reveal molecular-scale principles to help the development of wet-resistant adhesives.

  3. Mussel adhesion is dictated by time-regulated secretion and molecular conformation of mussel adhesive proteins

    NASA Astrophysics Data System (ADS)

    Petrone, Luigi; Kumar, Akshita; Sutanto, Clarinda N.; Patil, Navinkumar J.; Kannan, Srinivasaraghavan; Palaniappan, Alagappan; Amini, Shahrouz; Zappone, Bruno; Verma, Chandra; Miserez, Ali

    2015-10-01

    Interfacial water constitutes a formidable barrier to strong surface bonding, hampering the development of water-resistant synthetic adhesives. Notwithstanding this obstacle, the Asian green mussel Perna viridis attaches firmly to underwater surfaces via a proteinaceous secretion (byssus). Extending beyond the currently known design principles of mussel adhesion, here we elucidate the precise time-regulated secretion of P. viridis mussel adhesive proteins. The vanguard 3,4-dihydroxy-L-phenylalanine (Dopa)-rich protein Pvfp-5 acts as an adhesive primer, overcoming repulsive hydration forces by displacing surface-bound water and generating strong surface adhesion. Using homology modelling and molecular dynamics simulations, we find that all mussel adhesive proteins are largely unordered, with Pvfp-5 adopting a disordered structure and elongated conformation whereby all Dopa residues reside on the protein surface. Time-regulated secretion and structural disorder of mussel adhesive proteins appear essential for optimizing extended nonspecific surface interactions and byssus' assembly. Our findings reveal molecular-scale principles to help the development of wet-resistant adhesives.

  4. Mussel adhesion is dictated by time-regulated secretion and molecular conformation of mussel adhesive proteins

    PubMed Central

    Petrone, Luigi; Kumar, Akshita; Sutanto, Clarinda N.; Patil, Navinkumar J.; Kannan, Srinivasaraghavan; Palaniappan, Alagappan; Amini, Shahrouz; Zappone, Bruno; Verma, Chandra; Miserez, Ali

    2015-01-01

    Interfacial water constitutes a formidable barrier to strong surface bonding, hampering the development of water-resistant synthetic adhesives. Notwithstanding this obstacle, the Asian green mussel Perna viridis attaches firmly to underwater surfaces via a proteinaceous secretion (byssus). Extending beyond the currently known design principles of mussel adhesion, here we elucidate the precise time-regulated secretion of P. viridis mussel adhesive proteins. The vanguard 3,4-dihydroxy-L-phenylalanine (Dopa)-rich protein Pvfp-5 acts as an adhesive primer, overcoming repulsive hydration forces by displacing surface-bound water and generating strong surface adhesion. Using homology modelling and molecular dynamics simulations, we find that all mussel adhesive proteins are largely unordered, with Pvfp-5 adopting a disordered structure and elongated conformation whereby all Dopa residues reside on the protein surface. Time-regulated secretion and structural disorder of mussel adhesive proteins appear essential for optimizing extended nonspecific surface interactions and byssus' assembly. Our findings reveal molecular-scale principles to help the development of wet-resistant adhesives. PMID:26508080

  5. Urea modified cottonseed protein adhesive for wood composite products

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Cottonseed protein has the potential to be used as renewable and environmentally friendly adhesives in wood products industry. However, the industry application was limited by its low mechanical properties, low water resistance and viscosity. In this work, urea modified cottonseed protein adhesive w...

  6. Investigation of modified cottonseed protein adhesives for wood composites

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Several modified cottonseed protein isolates were studied and compared to corresponding soy protein isolates for their adhesive properties when bonded to wood composites. Modifications included treatments with alkali, guanidine hydrochloride, sodium dodecyl sulfate (SDS), and urea. Wood composites...

  7. Gene Expression Regulation by the Curli Activator CsgD Protein: Modulation of Cellulose Biosynthesis and Control of Negative Determinants for Microbial Adhesion

    PubMed Central

    Brombacher, Eva; Baratto, Andrea; Dorel, Corinne; Landini, Paolo

    2006-01-01

    Curli fibers, encoded by the csgBAC genes, promote biofilm formation in Escherichia coli and other enterobacteria. Curli production is dependent on the CsgD transcription activator, which also promotes cellulose biosynthesis. In this study, we investigated the effects of CsgD expression from a weak constitutive promoter in the biofilm formation-deficient PHL565 strain of E. coli. We found that despite its function as a transcription activator, the CsgD protein is localized in the cytoplasmic membrane. Constitutive CsgD expression promotes biofilm formation by PHL565 and activates transcription from the csgBAC promoter; however, csgBAC expression remains dependent on temperature and the growth medium. Constitutive expression of the CsgD protein results in altered transcription patterns for at least 24 novel genes, in addition to the previously identified CsgD-dependent genes. The cspA and fecR genes, encoding regulatory proteins responding to cold shock and to iron, respectively, and yoaD, encoding a putative negative regulator of cellulose biosynthesis, were found to be some of the novel CsgD-regulated genes. Consistent with the predicted functional role, increased expression of the yoaD gene negatively affects cell aggregation, while yoaD inactivation results in stimulation of cell aggregation and leads to increased cellulose production. Inactivation of fecR results in significant increases in both cell aggregation and biofilm formation, while the effects of cspA are not as strong in the conditions tested. Our results indicate that CsgD can modulate cellulose biosynthesis through activation of the yoaD gene. In addition, the positive effect of CsgD on biofilm formation might be enhanced by repression of the fecR gene. PMID:16513732

  8. Gene expression regulation by the Curli activator CsgD protein: modulation of cellulose biosynthesis and control of negative determinants for microbial adhesion.

    PubMed

    Brombacher, Eva; Baratto, Andrea; Dorel, Corinne; Landini, Paolo

    2006-03-01

    Curli fibers, encoded by the csgBAC genes, promote biofilm formation in Escherichia coli and other enterobacteria. Curli production is dependent on the CsgD transcription activator, which also promotes cellulose biosynthesis. In this study, we investigated the effects of CsgD expression from a weak constitutive promoter in the biofilm formation-deficient PHL565 strain of E. coli. We found that despite its function as a transcription activator, the CsgD protein is localized in the cytoplasmic membrane. Constitutive CsgD expression promotes biofilm formation by PHL565 and activates transcription from the csgBAC promoter; however, csgBAC expression remains dependent on temperature and the growth medium. Constitutive expression of the CsgD protein results in altered transcription patterns for at least 24 novel genes, in addition to the previously identified CsgD-dependent genes. The cspA and fecR genes, encoding regulatory proteins responding to cold shock and to iron, respectively, and yoaD, encoding a putative negative regulator of cellulose biosynthesis, were found to be some of the novel CsgD-regulated genes. Consistent with the predicted functional role, increased expression of the yoaD gene negatively affects cell aggregation, while yoaD inactivation results in stimulation of cell aggregation and leads to increased cellulose production. Inactivation of fecR results in significant increases in both cell aggregation and biofilm formation, while the effects of cspA are not as strong in the conditions tested. Our results indicate that CsgD can modulate cellulose biosynthesis through activation of the yoaD gene. In addition, the positive effect of CsgD on biofilm formation might be enhanced by repression of the fecR gene.

  9. MiR-7a is an important mediator in Fas-associated protein with death domain (FADD)-regulated expression of focal adhesion kinase (FAK)

    PubMed Central

    Liu, Yingting; Cui, Hongen; Huang, Xianjie; Zhu, Bo; Guan, Shengwen; Cheng, Wei; Lai, Yueyang; Zhang, Xiaoxin; Hua, Zi-Chun

    2016-01-01

    Fas-associated protein with death domain (FADD), a classical adaptor protein mediating apoptotic stimuli-induced cell death, has been reported to engage in several non-apoptotic processes such as T cell and cardiac development and tumorigenesis. Recently, there are several reports about the FADD's involvement in cell migration, however the underlying mechanism remains elusive. Here, we present a new finding that FADD could regulate the expression of FAK, a non-receptor protein tyrosine kinase overexpressed in many cancers, and played an important role in cell migration in murine MEF and melanoma cells with different metastatic potential, B16F10 and B16F1. Moreover, miR-7a, a tumor suppressor which prohibits cell migration and invasion, was up-regulated in FADD-deficient cells. And FAK was verified to be the direct target gene of miR-7a in B16F10 cells. Furthermore, we demonstrate that miR-7a was a necessary mediator in FADD-regulated FAK expression. In contrast to its classical apoptotic role, FADD interference could reduce the rate of cell migration, which could be rescued by inhibiting miR-7a expression. Taken together, our data provide a novel explanation regarding how FADD regulates cell migration in murine melanoma cells. PMID:27286445

  10. Adhesion of mussel foot proteins to different substrate surfaces

    PubMed Central

    Lu, Qingye; Danner, Eric; Waite, J. Herbert; Israelachvili, Jacob N.; Zeng, Hongbo; Hwang, Dong Soo

    2013-01-01

    Mussel foot proteins (mfps) have been investigated as a source of inspiration for the design of underwater coatings and adhesives. Recent analysis of various mfps by a surface forces apparatus (SFA) revealed that mfp-1 functions as a coating, whereas mfp-3 and mfp-5 resemble adhesive primers on mica surfaces. To further refine and elaborate the surface properties of mfps, the force–distance profiles of the interactions between thin mfp (i.e. mfp-1, mfp-3 or mfp-5) films and four different surface chemistries, namely mica, silicon dioxide, polymethylmethacrylate and polystyrene, were measured by an SFA. The results indicate that the adhesion was exquisitely dependent on the mfp tested, the substrate surface chemistry and the contact time. Such studies are essential for understanding the adhesive versatility of mfps and related/similar adhesion proteins, and for translating this versatility into a new generation of coatings and (including in vivo) adhesive materials. PMID:23173195

  11. Redundant control of migration and adhesion by ERM proteins in vascular smooth muscle cells

    SciTech Connect

    Baeyens, Nicolas; Latrache, Iman; Yerna, Xavier; Noppe, Gauthier; Horman, Sandrine; Morel, Nicole

    2013-11-22

    Highlights: •The three ERM proteins are expressed in vascular smooth muscle cell. •ERM depletion inhibited PDGF-evoked migration redundantly. •ERM depletion increased cell adhesion redundantly. •ERM depletion did not affect PDGF-evoked Ca signal, Rac1 activation, proliferation. •ERM proteins control PDGF-induced migration by regulating adhesion. -- Abstract: Ezrin, radixin, and moesin possess a very similar structure with a C-terminal actin-binding domain and a N-terminal FERM interacting domain. They are known to be involved in cytoskeleton organization in several cell types but their function in vascular smooth muscle cells (VSMC) is still unknown. The aim of this study was to investigate the role of ERM proteins in cell migration induced by PDGF, a growth factor involved in pathophysiological processes like angiogenesis or atherosclerosis. We used primary cultured VSMC obtained from rat aorta, which express the three ERM proteins. Simultaneous depletion of the three ERM proteins with specific siRNAs abolished the effects of PDGF on cell architecture and migration and markedly increased cell adhesion and focal adhesion size, while these parameters were only slightly affected by depletion of ezrin, radixin or moesin alone. Rac1 activation, cell proliferation, and Ca{sup 2+} signal in response to PDGF were unaffected by ERM depletion. These results indicate that ERM proteins exert a redundant control on PDGF-induced VSMC migration by regulating focal adhesion turn-over and cell adhesion to substrate.

  12. Soy protein isolate molecular level contributions to bulk adhesive properties

    NASA Astrophysics Data System (ADS)

    Shera, Jeanne Norton

    Increasing environmental awareness and the recognized health hazards of formaldehyde-based resins has prompted a strong demand for environmentally-responsible adhesives for wood composites. Soy protein-based adhesives have been shown to be commercially viable with 90-day shelf stability and composite physical properties comparable to those of commercial formaldehyde-based particleboards. The main research focus is to isolate and characterize the molecular level features in soy protein isolate responsible for providing mechanical properties, storage stability, and water resistance during adhesive formulation, processing, and wood composite fabrication. Commercial composite board will be reviewed to enhance our understanding of the individual components and processes required for particleboard production. The levels of protein structure will be defined and an overview of current bio-based technology will be presented. In the process, the logic for utilizing soy protein as a sole binder in the adhesive will be reinforced. Variables such as adhesive components, pH, divalent ions, blend aging, protein molecular weight, formulation solids content, and soy protein functionalization will relate the bulk properties of soy protein adhesives to the molecular configuration of the soybean protein. This work has demonstrated that when intermolecular beta-sheet interactions and protein long-range order is disrupted, viscosity and mechanical properties decrease. Storage stability can be maintained through the stabilization of intermolecular beta-sheet interactions. When molecular weight is reduced through enzymatic digestion, long-range order is disrupted and viscosity and mechanical properties decrease accordingly. Processibility and physical properties must be balanced to increase solids while maintaining low viscosity, desirable mechanical properties, and adequate storage stability. The structure of the soybean protein must be related to the particleboard bulk mechanical

  13. Expression of integrins by human periodontal ligament and gingival fibroblasts and their involvement in fibroblast adhesion to enamel matrix-derived proteins.

    PubMed

    van der Pauw, M T M; Everts, V; Beertsen, W

    2002-10-01

    We showed recently that human periodontal ligament (PDL) and gingival fibroblasts adhere and spread on enamel matrix protein (EMP) coatings. In the present study, we investigated whether this interaction can be attributed to integrin expression. Human PDL and gingival fibroblasts were cultured for periods up to 24 h on EMP coatings, in the presence of synthetic RGD-containing peptide or an antibody against the beta1 integrin subunit. The cells were first cultured for 24 h under serum-free conditions and then cultured on EMP coatings for 48 h. Integrin expression levels were assessed by flow cytometry analysis. It was found that attachment and spreading on EMP was inhibited by the synthetic RGD-containing peptide, but not by a synthetic RGE-peptide. Both PDL and gingival fibroblasts showed expression of the integrin subunits, alpha2, alpha5, beta1, and the integrin, alphavbeta3. Incubation with an antibody against the beta1 subunit significantly inhibited the attachment and spreading of PDL and gingival fibroblasts on EMP coatings. We conclude that integrins are involved in the interaction of PDL and gingival fibroblasts with EMP.

  14. Spatial distribution of proteins in the quagga mussel adhesive apparatus.

    PubMed

    Rees, David J; Hanifi, Arash; Manion, Joseph; Gantayet, Arpita; Sone, Eli D

    2016-01-01

    The invasive freshwater mollusc Dreissena bugensis (quagga mussel) sticks to underwater surfaces via a proteinacious 'anchor' (byssus), consisting of a series of threads linked to adhesive plaques. This adhesion results in the biofouling of crucial underwater industry infrastructure, yet little is known about the proteins responsible for the adhesion. Here the identification of byssal proteins extracted from freshly secreted byssal material is described. Several new byssal proteins were observed by gel electrophoresis. Matrix-assisted laser desorption/ionization time-of-flight mass spectrometry was used to characterize proteins in different regions of the byssus, particularly those localized to the adhesive interface. Byssal plaques and threads contain in common a range of low molecular weight proteins, while several proteins with higher mass were observed only in the plaque. At the adhesive interface, a plaque-specific ~8.1 kDa protein had a relative increase in signal intensity compared to the bulk of the plaque, suggesting it may play a direct role in adhesion.

  15. Protein expression-yeast.

    PubMed

    Nielsen, Klaus H

    2014-01-01

    Yeast is an excellent system for the expression of recombinant eukaryotic proteins. Both endogenous and heterologous proteins can be overexpressed in yeast (Phan et al., 2001; Ton and Rao, 2004). Because yeast is easy to manipulate genetically, a strain can be optimized for the expression of a specific protein. Many eukaryotic proteins contain posttranslational modifications that can be performed in yeast but not in bacterial expression systems. In comparison with mammalian cell culture expression systems, growing yeast is both faster and less expensive, and large-scale cultures can be performed using fermentation. While several different yeast expression systems exist, this chapter focuses on the budding yeast Saccharomyces cerevisiae and will briefly describe some options to consider when selecting vectors and tags to be used for protein expression. Throughout this chapter, the expression and purification of yeast eIF3 is shown as an example alongside a general scheme outline.

  16. Focal adhesion protein abnormalities in myelodysplastic mesenchymal stromal cells

    SciTech Connect

    Aanei, Carmen Mariana; Eloae, Florin Zugun; Flandrin-Gresta, Pascale; Tavernier, Emmanuelle; Carasevici, Eugen; Guyotat, Denis; Campos, Lydia

    2011-11-01

    Direct cell-cell contact between haematopoietic progenitor cells (HPCs) and their cellular microenvironment is essential to maintain 'stemness'. In cancer biology, focal adhesion (FA) proteins are involved in survival signal transduction in a wide variety of human tumours. To define the role of FA proteins in the haematopoietic microenvironment of myelodysplastic syndromes (MDS), CD73-positive mesenchymal stromal cells (MSCs) were immunostained for paxillin, pFAK [Y{sup 397}], and HSP90{alpha}/{beta} and p130CAS, and analysed for reactivity, intensity and cellular localisation. Immunofluorescence microscopy allowed us to identify qualitative and quantitative differences, and subcellular localisation analysis revealed that in pathological MSCs, paxillin, pFAK [Y{sup 397}], and HSP90{alpha}/{beta} formed nuclear molecular complexes. Increased expression of paxillin, pFAK [Y{sup 397}], and HSP90{alpha}/{beta} and enhanced nuclear co-localisation of these proteins correlated with a consistent proliferative advantage in MSCs from patients with refractory anaemia with excess blasts (RAEB) and negatively impacted clonogenicity of HPCs. These results suggest that signalling via FA proteins could be implicated in HPC-MSC interactions. Further, because FAK is an HSP90{alpha}/{beta} client protein, these results suggest the utility of HSP90{alpha}/{beta} inhibition as a target for adjuvant therapy for myelodysplasia.

  17. A bioinspired elastin-based protein for a cytocompatible underwater adhesive.

    PubMed

    Brennan, M Jane; Kilbride, Bridget F; Wilker, Jonathan J; Liu, Julie C

    2017-04-01

    The development of adhesives that can be applied and create strong bonds underwater is a significant challenge for materials engineering. When the adhesive is intended for biomedical applications, further criteria, such as biocompatibility, must be met. Current biomedical adhesive technologies do not meet these needs. In response, we designed a bioinspired protein system that shows promise to achieve biocompatible underwater adhesion coupled with environmentally responsive behavior that is "smart" - that is, it can be tuned to suit a specific application. The material, ELY16, is constructed from an elastin-like polypeptide (ELP) that can be produced in high yields from Escherichia coli and can coacervate in response to environmental factors such as temperature, pH, and salinity. To confer wet adhesion, we utilized design principles from marine organisms such as mussels and sandcastle worms. When expressed, ELY16 is rich in tyrosine. Upon modification with the tyrosinase enzyme to form mELY16, the tyrosine residues are converted to 3,4-dihydroxyphenylalanine (DOPA). Both ELY16 and mELY16 exhibit cytocompatibility and significant dry adhesion strength (>2 MPa). Modification with DOPA increases protein adsorption to glass and provides moderate adhesion strength (∼240 kPa) in a highly humid environment. Furthermore, this ELP exhibits a tunable phase transition behavior that can be formulated to coacervate in physiological conditions and provides a convenient mechanism for application underwater. Finally, mELY16 possesses significantly higher adhesion strength in dry, humid, and underwater environments compared with a commercially available fibrin sealant. To our knowledge, mELY16 provides the strongest bonds of any rationally designed protein when used completely underwater, and its high yields make it more viable for commercial application compared to natural adhesive proteins. In conclusion, this ELP shows great potential to be a new "smart" underwater adhesive.

  18. Mussel-mimetic protein-based adhesive hydrogel.

    PubMed

    Kim, Bum Jin; Oh, Dongyeop X; Kim, Sangsik; Seo, Jeong Hyun; Hwang, Dong Soo; Masic, Admir; Han, Dong Keun; Cha, Hyung Joon

    2014-05-12

    Hydrogel systems based on cross-linked polymeric materials which could provide both adhesion and cohesion in wet environment have been considered as a promising formulation of tissue adhesives. Inspired by marine mussel adhesion, many researchers have tried to exploit the 3,4-dihydroxyphenylalanine (DOPA) molecule as a cross-linking mediator of synthetic polymer-based hydrogels which is known to be able to achieve cohesive hardening as well as adhesive bonding with diverse surfaces. Beside DOPA residue, composition of other amino acid residues and structure of mussel adhesive proteins (MAPs) have also been considered important elements for mussel adhesion. Herein, we represent a novel protein-based hydrogel system using DOPA-containing recombinant MAP. Gelation can be achieved using both oxdiation-induced DOPA quinone-mediated covalent and Fe(3+)-mediated coordinative noncovalent cross-linking. Fe(3+)-mediated hydrogels show deformable and self-healing viscoelastic behavior in rheological analysis, which is also well-reflected in bulk adhesion strength measurement. Quinone-mediated hydrogel has higher cohesive strength and can provide sufficient gelation time for easier handling. Collectively, our newly developed MAP hydrogel can potentially be used as tissue adhesive and sealant for future applications.

  19. Novel protein-repellent dental adhesive containing 2-methacryloyloxyethyl phosphorylcholine

    PubMed Central

    Zhang, Ning; Melo, Mary Anne S.; Bai, Yuxing; Xu, Hockin H. K.

    2015-01-01

    Objectives Biofilms at tooth-restoration margins can produce acids and cause secondary caries. A protein-repellent adhesive resin can potentially inhibition bacteria attachment and biofilm growth. However, there has been no report on protein-repellent dental resins. The objectives of this study were to develop a protein-repellent bonding agent incorporating 2-methacryloyloxyethyl phosphorylcholine (MPC), and to investigate its resistance to protein adsorption and biofilm growth for the first time. Methods MPC was incorporated into Scotchbond Multi-Purpose (SBMP) at 0%, 3.75%, 7.5%, 11.25%, and 15% by mass. Extracted human teeth were used to measure dentin shear bond strengths. Protein adsorption onto resins was determined by a micro bicinchoninic acid (BCA) method. A dental plaque microcosm biofilm model with human saliva as inoculum was used to measure biofilm metabolic activity and colony-forming unit (CFU) counts. Results Adding 7.5% MPC into primer and adhesive did not decrease the dentin bond strength, compared to control (p > 0.1). Incorporation of 7.5% of MPC achieved the lowest protein adsorption, which was 20-fold less than that of control. Incorporation of 7.5% of MPC greatly reduced bacterial adhesion, yielding biofilm total microorganism, total streptococci, and mutans streptococci CFU that were an order of magnitude less than control. Conclusions A protein-repellent dental adhesive resin was developed for the first time. Incorporation of MPC into primer and adhesive at 7.5% by mass greatly reduced the protein adsorption and bacterial adhesion, without compromising the dentin bond strength. The novel protein-repellent primer and adhesive are promising to inhibit biofilm formation and acid production, to protect the tooth-restoration margins and prevent secondary caries. PMID:25234652

  20. Adhesive proteins of stalked and acorn barnacles display homology with low sequence similarities.

    PubMed

    Jonker, Jaimie-Leigh; Abram, Florence; Pires, Elisabete; Varela Coelho, Ana; Grunwald, Ingo; Power, Anne Marie

    2014-01-01

    Barnacle adhesion underwater is an important phenomenon to understand for the prevention of biofouling and potential biotechnological innovations, yet so far, identifying what makes barnacle glue proteins 'sticky' has proved elusive. Examination of a broad range of species within the barnacles may be instructive to identify conserved adhesive domains. We add to extensive information from the acorn barnacles (order Sessilia) by providing the first protein analysis of a stalked barnacle adhesive, Lepas anatifera (order Lepadiformes). It was possible to separate the L. anatifera adhesive into at least 10 protein bands using SDS-PAGE. Intense bands were present at approximately 30, 70, 90 and 110 kilodaltons (kDa). Mass spectrometry for protein identification was followed by de novo sequencing which detected 52 peptides of 7-16 amino acids in length. None of the peptides matched published or unpublished transcriptome sequences, but some amino acid sequence similarity was apparent between L. anatifera and closely-related Dosima fascicularis. Antibodies against two acorn barnacle proteins (ab-cp-52k and ab-cp-68k) showed cross-reactivity in the adhesive glands of L. anatifera. We also analysed the similarity of adhesive proteins across several barnacle taxa, including Pollicipes pollicipes (a stalked barnacle in the order Scalpelliformes). Sequence alignment of published expressed sequence tags clearly indicated that P. pollicipes possesses homologues for the 19 kDa and 100 kDa proteins in acorn barnacles. Homology aside, sequence similarity in amino acid and gene sequences tended to decline as taxonomic distance increased, with minimum similarities of 18-26%, depending on the gene. The results indicate that some adhesive proteins (e.g. 100 kDa) are more conserved within barnacles than others (20 kDa).

  1. Adhesive Proteins of Stalked and Acorn Barnacles Display Homology with Low Sequence Similarities

    PubMed Central

    Jonker, Jaimie-Leigh; Abram, Florence; Pires, Elisabete; Varela Coelho, Ana; Grunwald, Ingo; Power, Anne Marie

    2014-01-01

    Barnacle adhesion underwater is an important phenomenon to understand for the prevention of biofouling and potential biotechnological innovations, yet so far, identifying what makes barnacle glue proteins ‘sticky’ has proved elusive. Examination of a broad range of species within the barnacles may be instructive to identify conserved adhesive domains. We add to extensive information from the acorn barnacles (order Sessilia) by providing the first protein analysis of a stalked barnacle adhesive, Lepas anatifera (order Lepadiformes). It was possible to separate the L. anatifera adhesive into at least 10 protein bands using SDS-PAGE. Intense bands were present at approximately 30, 70, 90 and 110 kilodaltons (kDa). Mass spectrometry for protein identification was followed by de novo sequencing which detected 52 peptides of 7–16 amino acids in length. None of the peptides matched published or unpublished transcriptome sequences, but some amino acid sequence similarity was apparent between L. anatifera and closely-related Dosima fascicularis. Antibodies against two acorn barnacle proteins (ab-cp-52k and ab-cp-68k) showed cross-reactivity in the adhesive glands of L. anatifera. We also analysed the similarity of adhesive proteins across several barnacle taxa, including Pollicipes pollicipes (a stalked barnacle in the order Scalpelliformes). Sequence alignment of published expressed sequence tags clearly indicated that P. pollicipes possesses homologues for the 19 kDa and 100 kDa proteins in acorn barnacles. Homology aside, sequence similarity in amino acid and gene sequences tended to decline as taxonomic distance increased, with minimum similarities of 18–26%, depending on the gene. The results indicate that some adhesive proteins (e.g. 100 kDa) are more conserved within barnacles than others (20 kDa). PMID:25295513

  2. Intercellular Adhesion Molecule-1 Expression by Skeletal Muscle Cells Augments Myogenesis

    PubMed Central

    Goh, Qingnian; Dearth, Christopher L.; Corbett, Jacob T.; Pierre, Philippe; Chadee, Deborah N.; Pizza, Francis X.

    2014-01-01

    We previously demonstrated that the expression of intercellular adhesion molecule-1 (ICAM-1) by skeletal muscle cells after muscle overload contributes to ensuing regenerative and hypertrophic processes in skeletal muscle. The objective of the present study is to reveal mechanisms through which skeletal muscle cell expression of ICAM-1 augments regenerative and hypertrophic processes of myogenesis. This was accomplished by genetically engineering C2C12 myoblasts to stably express ICAM-1, and by inhibiting the adhesive and signaling functions of ICAM-1 through the use of a neutralizing antibody or cell penetrating peptide, respectively. Expression of ICAM-1 by cultured skeletal muscle cells augmented myoblast-myoblast adhesion, myotube formation, myonuclear number, myotube alignment, myotube-myotube fusion, and myotube size without influencing the ability of myoblasts to proliferate or differentiate. ICAM-1 augmented myotube formation, myonuclear accretion, and myotube alignment through a mechanism involving adhesion-induced activation of ICAM-1 signaling, as these dependent measures were reduced via antibody and peptide inhibition of ICAM-1. The adhesive and signaling functions of ICAM-1 also facilitated myotube hypertrophy through a mechanism involving myotube-myotube fusion, protein synthesis, and Akt/p70s6k signaling. Our findings demonstrate that ICAM-1 expression by skeletal muscle cells augments myogenesis, and establish a novel mechanism through which the inflammatory response facilitates growth processes in skeletal muscle. PMID:25281303

  3. Intercellular adhesion molecule-1 expression by skeletal muscle cells augments myogenesis

    SciTech Connect

    Goh, Qingnian; Dearth, Christopher L.; Corbett, Jacob T.; Pierre, Philippe; Chadee, Deborah N.; Pizza, Francis X.

    2015-02-15

    We previously demonstrated that the expression of intercellular adhesion molecule-1 (ICAM-1) by skeletal muscle cells after muscle overload contributes to ensuing regenerative and hypertrophic processes in skeletal muscle. The objective of the present study is to reveal mechanisms through which skeletal muscle cell expression of ICAM-1 augments regenerative and hypertrophic processes of myogenesis. This was accomplished by genetically engineering C2C12 myoblasts to stably express ICAM-1, and by inhibiting the adhesive and signaling functions of ICAM-1 through the use of a neutralizing antibody or cell penetrating peptide, respectively. Expression of ICAM-1 by cultured skeletal muscle cells augmented myoblast–myoblast adhesion, myotube formation, myonuclear number, myotube alignment, myotube–myotube fusion, and myotube size without influencing the ability of myoblasts to proliferate or differentiate. ICAM-1 augmented myotube formation, myonuclear accretion, and myotube alignment through a mechanism involving adhesion-induced activation of ICAM-1 signaling, as these dependent measures were reduced via antibody and peptide inhibition of ICAM-1. The adhesive and signaling functions of ICAM-1 also facilitated myotube hypertrophy through a mechanism involving myotube–myotube fusion, protein synthesis, and Akt/p70s6k signaling. Our findings demonstrate that ICAM-1 expression by skeletal muscle cells augments myogenesis, and establish a novel mechanism through which the inflammatory response facilitates growth processes in skeletal muscle. - Highlights: • We examined mechanisms through which skeletal muscle cell expression of ICAM-1 facilitates events of in vitro myogenesis. • Expression of ICAM-1 by cultured myoblasts did not influence their ability to proliferate or differentiate. • Skeletal muscle cell expression of ICAM-1 augmented myoblast fusion, myotube alignment, myotube–myotube fusion, and myotube size. • ICAM-1 augmented myogenic processes through

  4. Dominant-negative effect on adhesion by myelin Po protein truncated in its cytoplasmic domain

    PubMed Central

    1996-01-01

    The myelin Po protein is believed to hold myelin together via interactions of both its extracellular and cytoplasmic domains. We have already shown that the extracellular domains of Po can interact in a homophilic manner (Filbin, M.T., F.S. Walsh, B.D. Trapp, J.A. Pizzey, and G.I. Tennekoon. 1990. Nature (Lond.). 344:871-872). In addition, we have shown that for this homophilic adhesion to take place, the cytoplasmic domain of Po must be intact and most likely interacting with the cytoskeleton; Po proteins truncated in their cytoplasmic domains are not adhesive (Wong, M.H., and M.T. Filbin, 1994. J. Cell Biol. 126:1089-1097). To determine if the presence of these truncated forms of Po could have an effect on the functioning of the full-length Po, we coexpressed both molecules in CHO cells. The adhesiveness of CHO cells expressing both full-length Po and truncated Po was then compared to cells expressing only full-length Po. In these coexpressors, both the full-length and the truncated Po proteins were glycosylated. They reached the surface of the cell in approximately equal amounts as shown by an ELISA and surface labeling, followed by immunoprecipitation. Furthermore, the amount of full-length Po at the cell surface was equivalent to other cell lines expressing only full-length Po that we had already shown to be adhesive. Therefore, there should be sufficient levels of full-length Po at the surface of these coexpressors to measure adhesion of Po. However, as assessed by an aggregation assay, the coexpressors were not adhesive. By 60 min they had not formed large aggregates and were indistinguishable from the control transfected cells not expressing Po. In contrast, in the same time, the cells expressing only the full-length Po had formed large aggregates. This indicates that the truncated forms of Po have a dominant-negative effect on the adhesiveness of the full-length Po. Furthermore, from cross-linking studies, full-length Po, when expressed alone but not when

  5. Nanoscale adhesion forces between enamel pellicle proteins and hydroxyapatite.

    PubMed

    Vukosavljevic, D; Hutter, J L; Helmerhorst, E J; Xiao, Y; Custodio, W; Zaidan, F C; Oppenheim, F G; Siqueira, W L

    2014-05-01

    The acquired enamel pellicle (AEP) is important for minimizing the abrasion caused by parafunctional conditions as they occur, for instance, during bruxism. It is a remarkable feature of the AEP that a protein/peptide film can provide enough protection in normofunction to prevent teeth from abrasion and wear. Despite its obvious critical role in the protection of tooth surfaces, the essential adhesion features of AEP proteins on the enamel surface are poorly characterized. The objective of this study was to measure the adhesion force between histatin 5, a primary AEP component, and hydroxyapatite (HA) surfaces. Both biotinylated histatin 5 and biotinylated human serum albumin were allowed to adsorb to streptavidin-coated silica microspheres attached to atomic force microscope (AFM) cantilevers. A multimode AFM with a Nanoscope IIIa controller was used to measure the adhesion force between protein-functionalized silica microspheres attached to cantilever tips and the HA surface. The imaging was performed in tapping mode with a Si3N4 AFM cantilever, while the adhesion forces were measured in AFM contact mode. A collection of force-distance curves (~3,000/replicate) was obtained to generate histograms from which the adhesion forces between histatin 5 or albumin and the HA surface were measured. We found that histatin 5 exhibited stronger adhesion forces (90% >1.830 nN) to the HA surface than did albumin (90% > 0.282 nN). This study presents an objective approach to adhesion force measurements between histatin 5 and HA, and provides the experimental basis for measuring the same parameters for other AEP constituents. Such knowledge will help in the design of synthetic proteins and peptides with preventive and therapeutic benefits for tooth enamel.

  6. Candida albicans stimulates cytokine production and leukocyte adhesion molecule expression by endothelial cells.

    PubMed Central

    Filler, S G; Pfunder, A S; Spellberg, B J; Spellberg, J P; Edwards, J E

    1996-01-01

    Endothelial cells have the potential to influence significantly the host immune response to blood-borne microbial pathogens, such as Candida albicans. We investigated the ability (of this organism to stimulate endothelial cell responses relevant to host defense in vitro. Infection with C. albicans induced endothelial cells to express mRNAs encoding E-selectin, intercellular adhesion molecule 1, vascular cell adhesion molecule 1, interleukin 6, interleukin 8, monocyte chemoattractant protein 1, and inducible cyclooxygenase (cox2). All three leukocyte adhesion molecule proteins were expressed on the surfaces of the endothelial cells after 8 h of exposure to C. albicans. An increase in secretion of all three cytokines was found after 12 h of infection. Cytochalasin D inhibited accumulation of the endothelial cell cytokine and leukocyte adhesion molecule mRNAs in response to C. albicans, suggesting that endothelial cell phagocytosis of the organism is required to induce this response. Live Candida tropicalis, Candida glabrata, a nongerminating strain of C. albicans, and killed C. albicans did not stimulate the expression of any of the cytokine or leukocyte adhesion molecule mRNAs. These findings indicate that a factor associated with live, germinating C. albicans is required for induction of endothelial cell mRNA expression. Furthermore, since endothelial cells phagocytize killed C. albicans, phagocytosis is likely necessary but not sufficient for this organism to stimulate mRNA accumulation. In conclusion, the secretion of proinflammatory cytokines and expression of leukocyte adhesion molecules by endothelial cells in response to C. albicans could enhance the host defense against this organism by contributing to the recruitment of activated leukocytes to sites of intravascular infection. PMID:8698486

  7. The molecular mechanism of mediation of adsorbed serum proteins to endothelial cells adhesion and growth on biomaterials.

    PubMed

    Yang, Dayun; Lü, Xiaoying; Hong, Ying; Xi, Tingfei; Zhang, Deyuan

    2013-07-01

    To explore molecular mechanism of mediation of adsorbed proteins to cell adhesion and growth on biomaterials, this study examined endothelial cell adhesion, morphology and viability on bare and titanium nitride (TiN) coated nickel titanium (NiTi) alloys and chitosan film firstly, and then identified the type and amount of serum proteins adsorbed on the three surfaces by proteomic technology. Subsequently, the mediation role of the identified proteins to cell adhesion and growth was investigated with bioinformatics analyses, and further confirmed by a series of cellular and molecular biological experiments. Results showed that the type and amount of adsorbed serum proteins associated with cell adhesion and growth was obviously higher on the alloys than on the chitosan film, and these proteins mediated endothelial cell adhesion and growth on the alloys via four ways. First, proteins such as adiponectin in the adsorbed protein layer bound with cell surface receptors to generate signal transduction, which activated cell surface integrins through increasing intracellular calcium level. Another way, thrombospondin 1 in the adsorbed protein layer promoted TGF-β signaling pathway activation and enhanced integrins expression. The third, RGD sequence containing proteins such as fibronectin 1, vitronectin and thrombospondin 1 in the adsorbed protein layer bound with activated integrins to activate focal adhesion pathway, increased focal adhesion formation and actin cytoskeleton organization and mediated cell adhesion and spreading. In addition, the activated focal adhesion pathway promoted the expression of cell growth related genes and resulted in cell proliferation. The fourth route, coagulation factor II (F2) and fibronectin 1 in the adsorbed protein layer bound with cell surface F2 receptor and integrin, activated regulation of actin cytoskeleton pathway and regulated actin cytoskeleton organization.

  8. The roles of Tenascin C and Fibronectin 1 in adhesive capsulitis: a pilot gene expression study

    PubMed Central

    Cohen, Carina; Leal, Mariana Ferreira; Belangero, Paulo Santoro; Figueiredo, Eduardo Antônio; Smith, Marília Cardoso; Andreoli, Carlos Vicente; de Castro Pochini, Alberto; Cohen, Moises; Ejnisman, Benno; Faloppa, Flávio

    2016-01-01

    OBJECTIVES: We evaluated mRNA expression levels of genes that encode TGF-β1; the TGF-β1 receptor; the collagen-modifying enzymes LOX, PLOD1, and PLOD2; and the extracellular matrix proteins COMP, FN1, TNC and TNXB in synovial/capsule specimens from patients with idiopathic adhesive capsulitis. Possible associations between the measured mRNA levels and clinical parameters were also investigated. METHODS: We obtained glenohumeral joint synovium/capsule specimens from 9 patients with idiopathic adhesive capsulitis who had not shown improvement in symptoms after 5 months of physiotherapy. Adhesive capsulitis was confirmed in all patients by magnetic resonance imaging. We also obtained specimens from 8 control patients who had underwent surgery for acute acromioclavicular joint dislocation and who had radiological indication of glenohumeral capsule alteration based on arthroscopic evaluation. mRNA expression in the synovium/capsule specimens was analyzed by quantitative reverse transcription PCR. The B2M and HPRT1 genes were used as references to normalize target gene expression in the shoulder tissue samples. RESULTS: The synovium/capsule samples from the patients with adhesive capsulitis had significantly higher TNC and FN1 expression than those from the controls. Additionally, symptom duration directly correlated with expression of TGFβ1 receptor I. CONCLUSION: Elevated levels of TNC and FN1 expression may be a marker of capsule injury. Upregulation of TGFβ1 receptor I seems to be dependent on symptom duration; therefore, TGFβ signaling may be involved in adhesive capsulitis. As such, TNC, FN1 and TGFβ1 receptor I may also play roles in adhesive capsulitis by contributing to capsule inflammation and fibrosis. PMID:27438566

  9. Functional Mineralocorticoid Receptors in Human Vascular Endothelial Cells Regulate ICAM-1 Expression and Promote Leukocyte Adhesion

    PubMed Central

    Caprio, Massimiliano; Newfell, Brenna G.; la Sala, Andrea; Baur, Wendy; Fabbri, Andrea; Rosano, Giuseppe; Mendelsohn, Michael E.; Jaffe, Iris Z.

    2008-01-01

    In clinical trials, aldosterone antagonists decrease cardiovascular mortality and ischemia by unknown mechanisms. The steroid hormone aldosterone acts by binding to the mineralocorticoid receptor (MR), a ligand-activated transcription factor. In humans, aldosterone causes MR-dependent endothelial cell (EC) dysfunction and in animal models, aldosterone increases vascular macrophage infiltration and atherosclerosis. MR antagonists inhibit these effects without changing blood pressure, suggesting a direct role for vascular MR in EC function and atherosclerosis. Whether human vascular EC express functional MR is not known. Here we show that human coronary artery and aortic EC express MR mRNA and protein and that EC MR mediates aldosterone-dependent gene transcription. Human EC also express the enzyme 11-beta hydroxysteroid dehydrogenase-2(11βHSD2) and inhibition of 11βHSD2 in aortic EC enhances gene transactivation by cortisol, supporting that EC 11βHSD2 is functional. Furthermore, aldosterone stimulates transcription of the proatherogenic leukocyte-EC adhesion molecule Intercellular Adhesion Molecule-1(ICAM1) gene and protein expression on human coronary artery EC, an effect inhibited by the MR antagonist spironolactone and by MR knock-down with siRNA. Cell adhesion assays demonstrate that aldosterone promotes leukocyte-EC adhesion, an effect that is inhibited by spironolactone and ICAM1 blocking antibody, supporting that aldosterone induction of EC ICAM1 surface expression via MR mediates leukocyte-EC adhesion. These data show that aldosterone activates endogenous EC MR and proatherogenic gene expression in clinically important human EC. These studies describe a novel mechanism by which aldosterone may influence ischemic cardiovascular events and support a new explanation for the decrease in ischemic events in patients treated with aldosterone antagonists. PMID:18467630

  10. Developmental regulation of the adhesive and enzymatic activity of vascular adhesion protein-1 (VAP-1) in humans.

    PubMed

    Salmi, Marko; Jalkanen, Sirpa

    2006-09-01

    Vascular adhesion protein-1 (VAP-1) is a homodimeric glycoprotein that belongs to a unique subgroup of cell-surface-expressed oxidases. In adults, endothelial VAP-1 supports leukocyte rolling, firm adhesion, and transmigration in both enzyme activity-dependent and enzyme activity-independent manner. Here we studied the induction and function of VAP-1 during human ontogeny. We show that VAP-1 is already found in the smooth muscle at embryonic week 7. There are marked time-dependent switches in VAP-1 expression in the sinusoids of the liver, in the peritubular capillaries of the kidney, in the capillaries of the heart, and in the venules in the lamina propria of the gut. Fetal VAP-1 is dimerized, and it is enzymatically active. VAP-1 in fetal-type venules is able to bind cord blood lymphocytes. Also, adenovirally transfected VAP-1 on human umbilical vein endothelial cells is involved in rolling and firm adhesion of cord blood lymphocytes under conditions of physiologic shear stress. We conclude that VAP-1 is synthesized from early on in human vessels and it is functionally intact already before birth. Thus, VAP-1 may contribute critically to the oxidase activities in utero, and prove important for lymphocyte trafficking during human ontogeny.

  11. The coffee diterpene kahweol inhibits tumor necrosis factor-{alpha}-induced expression of cell adhesion molecules in human endothelial cells

    SciTech Connect

    Kim, Hyung Gyun; Kim, Ji Young; Hwang, Yong Pil; Lee, Kyung Jin; Lee, Kwang Youl; Kim, Dong Hee; Kim, Dong Hyun; Jeong, Hye Gwang . E-mail: hgjeong@chosun.ac.kr

    2006-12-15

    Endothelial cells produce adhesion molecules after being stimulated with various inflammatory cytokines. These adhesion molecules play an important role in the development of atherogenesis. Recent studies have highlighted the chemoprotective and anti-inflammatory effects of kahweol, a coffee-specific diterpene. This study examined the effects of kahweol on the cytokine-induced monocyte/human endothelial cell interaction, which is a crucial early event in atherogenesis. Kahweol inhibited the adhesion of TNF{alpha}-induced monocytes to endothelial cells and suppressed the TNF{alpha}-induced protein and mRNA expression of the cell adhesion molecules, VCAM-1 and ICAM-1. Furthermore, kahweol inhibited the TNF{alpha}-induced JAK2-PI3K/Akt-NF-{kappa}B activation pathway in these cells. Overall, kahweol has anti-inflammatory and anti-atherosclerotic activities, which occurs partly by down-regulating the pathway that affects the expression and interaction of the cell adhesion molecules on endothelial cells.

  12. Expression of adhesion molecules and chemotactic cytokines in cultured human mesothelial cells.

    PubMed

    Jonjić, N; Peri, G; Bernasconi, S; Sciacca, F L; Colotta, F; Pelicci, P; Lanfrancone, L; Mantovani, A

    1992-10-01

    The mesothelium is a flat epithelial lining of serous cavities that could gate the traffic of molecules and cells between the circulation and these body compartments. The present study was designed to elucidate the capacity of mesothelial cells to express adhesion molecules and chemoattractant cytokines, two fundamental mechanisms of regulation of leukocyte recruitment. Cultured human mesothelial cells express appreciable levels of intercellular adhesion molecule 1 (ICAM-1) and vascular cell adhesion molecule 1 (VCAM-1), and these were increased by in vitro exposure to tumor necrosis factor (TNF), interferon gamma (IFN-gamma), or TNF and IFN-gamma. Interleukin 1 (IL-1) was a less consistent stimulus for adhesion molecule expression in vitro. Unlike endothelial cells, used as a reference cell population, resting or stimulated mesothelial cells did not express E-selectin and ICAM-2, as assessed by flow cytometry. Analysis of VCAM-1 mRNA by reverse transcriptase and polymerase chain reaction using appropriate primers revealed that mesothelial cells expressed both the seven- and the six-Ig domain transcripts, with predominance of the longer species. Monocytes bound appreciably to "resting" and, to a greater extent, to stimulated mesothelial cells. Monocytes exposed to IFN-gamma and lipopolysaccharide, used as prototypic activation signals, showed increased capacity to bind mesothelial cells. Anti-CD18 monoclonal antibody significantly inhibited binding of monocytes to mesothelial cells, and this blocking effect was amplified by anti-very late antigen 4. Mesothelial cells were able to express the chemotactic cytokines IL-8 and monocyte chemotactic protein 1 at the mRNA and protein levels. These results indicate that mesothelial cells can express a set of adhesion molecules (ICAM-1 and VCAM-1) overlapping with, but distinct from, that expressed in vascular endothelium (ICAM-1, ICAM-2, VCAM-1, E-selectin), and that these are functionally relevant for interacting with

  13. Secreted Frizzled-related protein 1 (sFRP1) regulates spermatid adhesion in the testis via dephosphorylation of focal adhesion kinase and the nectin-3 adhesion protein complex

    PubMed Central

    Wong, Elissa W. P.; Lee, Will M.; Cheng, C. Yan

    2013-01-01

    Development of spermatozoa in adult mammalian testis during spermatogenesis involves extensive cell migration and differentiation. Spermatogonia that reside at the basal compartment of the seminiferous epithelium differentiate into more advanced germ cell types that migrate toward the apical compartment until elongated spermatids are released into the tubule lumen during spermiation. Apical ectoplasmic specialization (ES; a testis-specific anchoring junction) is the only cell junction that anchors and maintains the polarity of elongating/elongated spermatids (step 8–19 spermatids) in the epithelium. Little is known regarding the signaling pathways that trigger the disassembly of the apical ES at spermiation. Here, we show that secreted Frizzled-related protein 1 (sFRP1), a putative tumor suppressor gene that is frequently down-regulated in multiple carcinomas, is a crucial regulatory protein for spermiation. The expression of sFRP1 is tightly regulated in adult rat testis to control spermatid adhesion and sperm release at spermiation. Down-regulation of sFRP1 during testicular development was found to coincide with the onset of the first wave of spermiation at approximately age 45 d postpartum, implying that sFRP1 might be correlated with elongated spermatid adhesion conferred by the apical ES before spermiation. Indeed, administration of sFRP1 recombinant protein to the testis in vivo delayed spermiation, which was accompanied by down-regulation of phosphorylated (p)-focal adhesion kinase (FAK)-Tyr397 and retention of nectin-3 adhesion protein at the apical ES. To further investigate the functional relationship between p-FAK-Tyr397 and localization of nectin-3, we overexpressed sFRP1 using lentiviral vectors in the Sertoli-germ cell coculture system. Consistent with the in vivo findings, overexpression of sFRP1 induced down-regulation of p-FAK-Tyr397, leading to a decline in phosphorylation of nectin-3. In summary, this report highlights the critical role of s

  14. Adhesions

    MedlinePlus

    Adhesions are bands of scar-like tissue. Normally, internal tissues and organs have slippery surfaces so they can shift easily as the body moves. Adhesions cause tissues and organs to stick together. They ...

  15. Adhesion

    MedlinePlus

    ... the intestines, adhesions can cause partial or complete bowel obstruction . Adhesions inside the uterine cavity, called Asherman syndrome , ... 1. Read More Appendicitis Asherman syndrome Glaucoma Infertility Intestinal obstruction Review Date 4/5/2016 Updated by: Irina ...

  16. [Neutrophils expression of adhesion molecules in diabetic nephropaty patients].

    PubMed

    Shcherban', T D

    2013-01-01

    CD11b and CD54 expression on neutrophils in patients with diabetic nephropathy (DN), arterial hypertension patients and healthy donors were examined. Development of DN associates with an increase of the number of CD11b and CD54 positive cells and violation of cellular co-operation. In the conditions of diabetic microenvironment expression of adhesion molecules rises substantially, what may characterized the mechanism of connection between hyperglycemia and vascular and tissues injury at DN. Authentication of morphological and biochemical markers of intercellular co-operation must in a prospect assist the deeper understanding of pathogenic mechanisms of DN.

  17. Reduced immunohistochemical expression of adhesion molecules in vitiligo skin biopsies.

    PubMed

    Reichert Faria, Adriane; Jung, Juliana Elizabeth; Silva de Castro, Caio César; de Noronha, Lucia

    2017-03-01

    Because defects in adhesion impairment seem to be involved in the etiopathogenesis of vitiligo, this study aimed to compare the immunohistochemical expression of several adhesion molecules in the epidermis of vitiligo and non lesional vitiligo skin. Sixty-six specimens of lesional and non lesional skin from 33 volunteers with vitiligo were evaluated by immunohistochemistry using anti-beta-catenin, anti-E-cadherin, anti-laminin, anti-beta1 integrin, anti-collagen IV, anti-ICAM-1 and anti-VCAM-1 antibodies. Biopsies of vitiligo skin demonstrated a significant reduction in the expression of laminin and integrin. The average value of the immunohistochemically positive reaction area of the vitiligo specimens was 3053.2μm(2), compared with the observed value of 3431.8μm(2) in non vitiligo skin (p=0.003) for laminin. The immuno-positive area was 7174.6μm(2) (vitiligo) and 8966.7μm(2) (non lesional skin) for integrin (p=0.042). A reduction in ICAM-1 and VCAM-1 expression in the basal layer of the epidermis in vitiligo samples was also observed (p=0.001 and p<0.001, respectively). However, no significant differences were observed with respect to the expression of beta-catenin, E-cadherin, and collagen IV between vitiligo and non lesional skin. Our results suggest that an impairment in adhesion exists in vitiligo skin, which is supported by the diminished immunohistochemical expression of laminin, beta1 integrin, ICAM-1 and VCAM-1.

  18. Silk Fibroin Aqueous-Based Adhesives Inspired by Mussel Adhesive Proteins.

    PubMed

    Burke, Kelly A; Roberts, Dane C; Kaplan, David L

    2016-01-11

    Silk fibroin from the domesticated silkworm Bombyx mori is a naturally occurring biopolymer with charged hydrophilic terminal regions that end-cap a hydrophobic core consisting of repeating sequences of glycine, alanine, and serine residues. Taking inspiration from mussels that produce proteins rich in L-3,4-dihydroxyphenylalanine (DOPA) to adhere to a variety of organic and inorganic surfaces, the silk fibroin was functionalized with catechol groups. Silk fibroin was selected for its high molecular weight, tunable mechanical and degradation properties, aqueous processability, and wide availability. The synthesis of catechol-functionalized silk fibroin polymers containing varying amounts of hydrophilic polyethylene glycol (PEG, 5000 g/mol) side chains was carried out to balance silk hydrophobicity with PEG hydrophilicity. The efficiency of the catechol functionalization reaction did not vary with PEG conjugation over the range studied, although tuning the amount of PEG conjugated was essential for aqueous solubility. Adhesive bonding and cell compatibility of the resulting materials were investigated, where it was found that incorporating as little as 6 wt % PEG prior to catechol functionalization resulted in complete aqueous solubility of the catechol conjugates and increased adhesive strength compared with silk lacking catechol functionalization. Furthermore, PEG-silk fibroin conjugates maintained their ability to form β-sheet secondary structures, which can be exploited to reduce swelling. Human mesenchymal stem cells (hMSCs) proliferated on the silks, regardless of PEG and catechol conjugation. These materials represent a protein-based approach to catechol-based adhesives, which we envision may find applicability as biodegradable adhesives and sealants.

  19. Heparanase expression upregulates platelet adhesion activity and thrombogenicity

    PubMed Central

    Österholm, Cecilia; Zhang, Xiao; Hedin, Ulf; Vlodavsky, Israel; Li, Jin-Ping

    2016-01-01

    Heparanase is an endo-glucuronidase that specifically cleaves heparan sulfate (HS) and heparin polysaccharides. The enzyme is expressed at low levels in normal tissues, but is often upregulated under pathological conditions such as cancer and inflammation. Normal human platelets express exceptionally high levels of heparanase, but the functional consequences of this feature remain unknown. We investigated functional roles of heparanase by comparing the properties of platelets expressing high (Hpa-tg) or low (Ctr) levels of heparanase. Upon activation, Hpa-tg platelets exhibited a much stronger adhesion activity as compared to Ctr platelets, likely contributing to a higher thrombotic activity in a carotid thrombosis model. Furthermore, we found concomitant upregulated expression of both heparanase and CD62P (P-selectin) upon activation of mouse and human platelets. As platelets play important roles in tumor metastasis, these findings indicate contribution of the platelet heparanase to hyper-thrombotic conditions often seen in patients with metastatic cancer. PMID:27129145

  20. Differential expression of cell adhesion molecules in an ionizing radiation-induced breast cancer model system.

    PubMed

    Calaf, Gloria M; Roy, Debasish; Narayan, Gopeshwar; Balajee, Adayabalam S

    2013-07-01

    Cell-cell adhesion is mediated by members of the cadherin-catenin system and among them E-cadherin and β-catenin are important adhesion molecules for epithelial cell function and preservation of tissue integrity. To investigate the importance of cell adhesion molecules in breast carcinogenesis, we developed an in vitro breast cancer model system wherein immortalized human breast epithelial cell line, MCF-10F, was malignantly transformed by exposure to low doses of high linear energy transfer (LET) α particle radiation (150 keV/µm) and subsequent growth in the presence or absence of 17β-estradiol. This model consisted of human breast epithelial cells in different stages of transformation: i) parental cell line MCF-10F; ii) MCF-l0F continuously grown with estradiol at 10(-8) (Estrogen); iii) a non-malignant cell line (Alpha3); and iv) a malignant and tumorigenic cell line (Alpha5) and the Tumor2 cell line derived from the nude mouse xenograft of the Alpha5 cell line. Expression levels of important cell adhesion molecules such as α-catenin, β-catenin, γ-catenin, E-cadherin and integrin were found to be higher at the protein level in the Alpha5 and Tumor2 cell lines relative to these levels in the non-tumorigenic MCF-10F, Estrogen and Alpha3 cell lines. In corroboration, cDNA expression analysis revealed elevated levels of genes involved in the cell adhesion function [E-cadherin, integrin β6 and desmocollin3 (DSc3)] in the Alpha5 and Tumor2 cell lines relative to the levels in the MCF-10F, Estrogen and Alpha3 cell lines. Collectively, our results suggest that cell adhesion molecules are expressed at higher levels in malignantly transformed breast epithelial cells relative to levels in non-malignant cells. However, reduced levels of adhesion molecules observed in the mouse xenograft-derived Tumor 2 cell line compared to the pre-tumorigenic Alpha5 cell line suggests that the altered expression levels of adhesion molecules depend on the tumor tissue

  1. Aire knockdown in medullary thymic epithelial cells affects Aire protein, deregulates cell adhesion genes and decreases thymocyte interaction.

    PubMed

    Pezzi, Nicole; Assis, Amanda Freire; Cotrim-Sousa, Larissa Cotrim; Lopes, Gabriel Sarti; Mosella, Maritza Salas; Lima, Djalma Sousa; Bombonato-Prado, Karina F; Passos, Geraldo Aleixo

    2016-09-01

    We demonstrate that even a partial reduction of Aire mRNA levels by siRNA-induced Aire knockdown (Aire KD) has important consequences to medullary thymic epithelial cells (mTECs). Aire knockdown is sufficient to reduce Aire protein levels, impair its nuclear location, and cause an imbalance in large-scale gene expression, including genes that encode cell adhesion molecules. These genes drew our attention because adhesion molecules are implicated in the process of mTEC-thymocyte adhesion, which is critical for T cell development and the establishment of central self-tolerance. Accordingly, we consider the following: 1) mTECs contribute to the elimination of self-reactive thymocytes through adhesion; 2) Adhesion molecules play a crucial role during physical contact between these cells; and 3) Aire is an important transcriptional regulator in mTECs. However, its role in controlling mTEC-thymocyte adhesion remains unclear. Because Aire controls adhesion molecule genes, we hypothesized that the disruption of its expression could influence mTEC-thymocyte interaction. To test this hypothesis, we used a murine Aire(+) mTEC cell line as a model system to reproduce mTEC-thymocyte adhesion in vitro. Transcriptome analysis of the mTEC cell line revealed that Aire KD led to the down-modulation of more than 800 genes, including those encoding for proteins involved in cell adhesion, i.e., the extracellular matrix constituent Lama1, the CAM family adhesion molecules Vcam1 and Icam4, and those that encode peripheral tissue antigens. Thymocytes co-cultured with Aire KD mTECs had a significantly reduced capacity to adhere to these cells. This finding is the first direct evidence that Aire also plays a role in controlling mTEC-thymocyte adhesion.

  2. Rolling adhesion kinematics of yeast engineered to express selectins.

    PubMed

    Bhatia, Sujata K; Swers, Jeffrey S; Camphausen, Raymond T; Wittrup, K Dane; Hammer, Daniel A

    2003-01-01

    Selectins are cell adhesion molecules that mediate capture of leukocytes on vascular endothelium as an essential component of the inflammatory response. Here we describe a method for yeast surface display of selectins, together with a functional assay that measures rolling adhesion of selectin-expressing yeast on a ligand-coated surface. E-selectin-expressing yeast roll specifically on surfaces bearing sialyl-Lewis-x ligands. Observation of yeast rolling dynamics at various stages of their life cycle indicates that the kinematics of yeast motion depends on the ratio of the bud radius to the parent radius (B/P). Large-budded yeast "walk" across the surface, alternately pivoting about bud and parent. Small-budded yeast "wobble" across the surface, with bud pivoting about parent. Tracking the bud location of budding yeast allows measurement of the angular velocity of the yeast particle. Comparison of translational and angular velocities of budding yeast demonstrates that selectin-expressing cells are rolling rather than slipping across ligand-coated surfaces.

  3. A genome-wide screen identifies conserved protein hubs required for cadherin-mediated cell–cell adhesion

    PubMed Central

    Toret, Christopher P.; D’Ambrosio, Michael V.; Vale, Ronald D.; Simon, Michael A.

    2014-01-01

    Cadherins and associated catenins provide an important structural interface between neighboring cells, the actin cytoskeleton, and intracellular signaling pathways in a variety of cell types throughout the Metazoa. However, the full inventory of the proteins and pathways required for cadherin-mediated adhesion has not been established. To this end, we completed a genome-wide (∼14,000 genes) ribonucleic acid interference (RNAi) screen that targeted Ca2+-dependent adhesion in DE-cadherin–expressing Drosophila melanogaster S2 cells in suspension culture. This novel screen eliminated Ca2+-independent cell–cell adhesion, integrin-based adhesion, cell spreading, and cell migration. We identified 17 interconnected regulatory hubs, based on protein functions and protein–protein interactions that regulate the levels of the core cadherin–catenin complex and coordinate cadherin-mediated cell–cell adhesion. Representative proteins from these hubs were analyzed further in Drosophila oogenesis, using targeted germline RNAi, and adhesion was analyzed in Madin–Darby canine kidney mammalian epithelial cell–cell adhesion. These experiments reveal roles for a diversity of cellular pathways that are required for cadherin function in Metazoa, including cytoskeleton organization, cell–substrate interactions, and nuclear and cytoplasmic signaling. PMID:24446484

  4. Differential effects of heme oxygenase isoforms on heme mediation of endothelial intracellular adhesion molecule 1 expression.

    PubMed

    Wagener, F A; da Silva, J L; Farley, T; de Witte, T; Kappas, A; Abraham, N G

    1999-10-01

    Heme oxygenase (HO), by catabolizing heme to bile pigments, down-regulates cellular hemoprotein, hemoglobin, and heme; the latter generates pro-oxidant products, including free radicals. Two HO isozymes, the products of distinct genes, have been described; HO-1 is the inducible isoform, whereas HO-2 is suggested to be constitutively expressed. We studied the inducing effect of several metal compounds (CoCl(2), stannic mesoporphyrin, and heme) on HO activity. Additionally, we studied HO-1 expression in experimental models of adhesion molecule expression produced by heme in endothelial cells, and the relationship of HO-1 expression to the induced adhesion molecules. Flow cytometry analysis showed that heme induces intracellular adhesion molecule 1 (ICAM-1) expression in a concentration (10-100 microM)- and time (1-24 h)-dependent fashion in human umbilical vein endothelial cells. Pretreatment with stannic mesoporphyrin, an inhibitor of HO activity, caused a 2-fold increase in heme-induced ICAM-1 expression. In contrast, HO induction by CoCl(2) decreased heme-induced ICAM-1 expression by 33%. To examine the contribution of HO-1 and HO-2 to endothelial HO activity, specific antisense oligonucleotides (ODNs) of each isoform were tested for their specificity to inhibit HO activity in cells exposed to heme. Endothelial cells exposed to heme elicited increased HO activity, which was prevented (70%) by HO-1 antisense ODNs. HO-2 antisense ODN inhibited heme-induced HO activity by 21%. Addition of HO-1 antisense ODNs prevented heme degradation and resulted in elevation of microsomal heme. Western blot analysis showed that HO-1 antisense ODNs selectively inhibited HO-1 protein and failed to inhibit HO-2 protein. Incubation of endothelial cells with HO-1 antisense enhanced heme-dependent increase of ICAM-1. In contrast, addition of HO-2 antisense to endothelial cells failed to increase adhesion molecules. The role of glutathione, an important antioxidant, was examined on heme

  5. Expression changes of nerve cell adhesion molecules L1 and semaphorin 3A after peripheral nerve injury

    PubMed Central

    He, Qian-ru; Cong, Meng; Chen, Qing-zhong; Sheng, Ya-feng; Li, Jian; Zhang, Qi; Ding, Fei; Gong, Yan-pei

    2016-01-01

    The expression of nerve cell adhesion molecule L1 in the neuronal growth cone of the central nervous system is strongly associated with the direction of growth of the axon, but its role in the regeneration of the peripheral nerve is still unknown. This study explored the problem in a femoral nerve section model in rats. L1 and semaphorin 3A mRNA and protein expressions were measured over the 4-week recovery period. Quantitative polymerase chain reaction showed that nerve cell adhesion molecule L1 expression was higher in the sensory nerves than in motor nerves at 2 weeks after injury, but vice versa for the expression of semaphorin 3A. Western blot assay results demonstrated that nerve cell adhesion molecule L1 expression was higher in motor nerves than in the sensory nerves at the proximal end after injury, but its expression was greater in the sensory nerves at 2 weeks. Semaphorin 3A expression was higher in the motor nerves than in the sensory nerves at 3 days and 1 week after injury. Nerve cell adhesion molecule L1 and semaphorin 3A expressions at the distal end were higher in the motor nerves than in the sensory nerves at 3 days, 1 and 2 weeks. Immunohistochemical staining results showed that nerve cell adhesion molecule L1 expression at the proximal end was greater in the sensory nerves than in the motor nerves; semaphorin 3A expression was higher in the motor nerves than in the sensory nerves at 2 weeks after injury. Taken together, these results indicated that nerve cell adhesion molecules L1 and semaphorin 3A exhibited different expression patterns at the proximal and distal ends of sensory and motor nerves, and play a coordinating role in neural chemotaxis regeneration. PMID:28197202

  6. Hyperketonemia increases monocyte adhesion to endothelial cells and is mediated by LFA-1 expression in monocytes and ICAM-1 expression in endothelial cells.

    PubMed

    Rains, Justin L; Jain, Sushil K

    2011-08-01

    Frequent episodes of hyperketonemia are associated with a higher incidence of vascular disease. The objective of this study was to examine the hypothesis that hyperketonemia increases monocyte-endothelial cell (EC) adhesion and the development of vascular disease in diabetes. Human U937 and THP-1 monocyte cell lines and human umbilical vein endothelial cells (HUVECs) were cultured with acetoacetate (AA) (0-10 mM) or β-hydroxybutyrate (BHB) (0-10 mM) for 24 h prior to evaluating adhesion and adhesion molecule expression. The results demonstrate a significant (P < 0.01) increase in both U937 and THP-1 adhesion to HUVEC monolayers treated with 4 mM AA compared with control. Equal concentrations of BHB resulted in similar increases in monocyte-EC adhesion. Similarly, treatments of AA or BHB to isolated monocytes from human blood also show increases in adhesion to endothelial cells. intercellular adhesion molecule-1 (ICAM-1) was significantly increased on the surface of HUVECs and an increase in total protein expression with AA treatment compared with control. The expression level of lymphocyte function-associated antigen-1 (LFA-1) was increased in monocytes treated with AA, and LFA-1 affinity was altered from low to high affinity following treatment with both AA and BHB. Monocyte adhesion could be blocked when cells were preincubated with an antibody to ICAM-1 or LFA-1. Results also show a significant increase in IL-8 and MCP-1 secretion in monocytes and HUVECs treated with 0-10 mM AA. These results suggest that hyperketonemia can induce monocyte adhesion to endothelial cells and that it is mediated via increased ICAM-1 expression in endothelial cells and increased expression and affinity of LFA-1 in monocytes.

  7. Hyperketonemia increases monocyte adhesion to endothelial cells and is mediated by LFA-1 expression in monocytes and ICAM-1 expression in endothelial cells

    PubMed Central

    Rains, Justin L.

    2011-01-01

    Frequent episodes of hyperketonemia are associated with a higher incidence of vascular disease. The objective of this study was to examine the hypothesis that hyperketonemia increases monocyte-endothelial cell (EC) adhesion and the development of vascular disease in diabetes. Human U937 and THP-1 monocyte cell lines and human umbilical vein endothelial cells (HUVECs) were cultured with acetoacetate (AA) (0–10 mM) or β-hydroxybutyrate (BHB) (0–10 mM) for 24 h prior to evaluating adhesion and adhesion molecule expression. The results demonstrate a significant (P < 0.01) increase in both U937 and THP-1 adhesion to HUVEC monolayers treated with 4 mM AA compared with control. Equal concentrations of BHB resulted in similar increases in monocyte-EC adhesion. Similarly, treatments of AA or BHB to isolated monocytes from human blood also show increases in adhesion to endothelial cells. intercellular adhesion molecule-1 (ICAM-1) was significantly increased on the surface of HUVECs and an increase in total protein expression with AA treatment compared with control. The expression level of lymphocyte function-associated antigen-1 (LFA-1) was increased in monocytes treated with AA, and LFA-1 affinity was altered from low to high affinity following treatment with both AA and BHB. Monocyte adhesion could be blocked when cells were preincubated with an antibody to ICAM-1 or LFA-1. Results also show a significant increase in IL-8 and MCP-1 secretion in monocytes and HUVECs treated with 0–10 mM AA. These results suggest that hyperketonemia can induce monocyte adhesion to endothelial cells and that it is mediated via increased ICAM-1 expression in endothelial cells and increased expression and affinity of LFA-1 in monocytes. PMID:21540444

  8. TSOL18/HP6-Tsol, an immunogenic Taenia solium oncospheral adhesion protein and potential protective antigen.

    PubMed

    Parkhouse, R Michael E; Bonay, Pedro; González, Luis Miguel; Ferrer, Elizabeth; Gárate, Teresa; Aguilar, Cruz M; Cortez A, Milagros M; Harrison, Leslie J S

    2008-04-01

    In this study, we employed Taenia solium mRNA extracted from a tapeworm of Venezuelan origin to clone express and test the recombinant protein of the T. solium homologue of the 18-kDa oncospheral adhesion molecule of Taenia saginata (HP6-Tsag/TSA18). We first confirm the conserved nature of the sequence of the T. solium homologue (TSOL18/HP6-Tsol) and demonstrate that the recombinant protein, which, as with its T. saginata homologue, is characterised by a fibronectin type III homology region, functions as an adhesion molecule. This emphasises the possible importance of TSOL18/HP6-Tsol in tissue invasion, thus providing a rational explanation for its efficacy as a vaccine. As protection against Taenia spp., oncospheres is antibody mediated, logically, therefore, TSOL18/HP6-Tsol may also serve as a diagnostic antigen, as is indeed the case for recombinant HP6-Tsag/TSA18.

  9. Dynamic expression of the cell adhesion molecule fasciclin I during embryonic development in Drosophila.

    PubMed

    McAllister, L; Goodman, C S; Zinn, K

    1992-05-01

    A number of different cell surface glycoproteins expressed in the central nervous system (CNS) have been identified in insects and shown to mediate cell adhesion in tissue culture systems. The fasciclin I protein is expressed on a subset of CNS axon pathways in both grasshopper and Drosophila. It consists of four homologous 150-amino acid domains which are unrelated to other sequences in the current databases, and is tethered to the cell surface by a glycosyl-phosphatidylinositol linkage. In this paper we examine in detail the expression of fasciclin I mRNA and protein during Drosophila embryonic development. We find that fasciclin I is expressed in several distinct patterns at different stages of development. In blastoderm embryos it is briefly localized in a graded pattern. During the germ band extended period its expression evolves through two distinct phases. Fasciclin I mRNA and protein are initially localized in a 14-stripe pattern which corresponds to segmentally repeated patches of neuroepithelial cells and neuroblasts. Expression then becomes confined to CNS and peripheral sensory (PNS) neurons. Fasciclin I is expressed on all PNS neurons, and this expression is stably maintained for several hours. In the CNS, fasciclin I is initially expressed on all commissural axons, but then becomes restricted to specific axon bundles. The early commissural expression pattern is not observed in grasshopper embryos, but the later bundle-specific pattern is very similar to that seen in grasshopper. The existence of an initial phase of expression on all commissural bundles helps to explain the loss-of-commissures phenotype of embryos lacking expression of both fasciclin I and of the D-abl tyrosine kinase. Fasciclin I is also expressed in several nonneural tissues in the embryo.

  10. Differential mouse-strain specific expression of Junctional Adhesion Molecule (JAM)-B in placental structures.

    PubMed

    Stelzer, Ina Annelies; Mori, Mayumi; DeMayo, Francesco; Lydon, John; Arck, Petra Clara; Solano, Maria Emilia

    2016-03-03

    The junctional adhesion molecule (JAM)-B, a member of the immunoglobulin superfamily, is involved in stabilization of interendothelial cell-cell contacts, formation of vascular tubes, homeostasis of stem cell niches and promotion of leukocyte adhesion and transmigration. In the human placenta, JAM-B protein is abundant and mRNA transcripts are enriched in first-trimester extravillous trophoblast in comparison to the villous trophoblast. We here aimed to elucidate the yet unexplored spatio-temporal expression of JAM-B in the mouse placenta. We investigated and semi-quantified JAM-B protein expression by immunohistochemistry in early post-implantation si tes and in mid- to late gestation placentae of various murine mating combinations. Surprisingly, the endothelium of the placental labyrinth was devoid of JAM-B expression. JAM-B was mainly present in spongiotrophoblast cells of the junctional zone, as well as in the fetal vessels of the chorionic plate, the umbilical cord and in maternal myometrial smooth muscle. We observed a strain-specific placental increase of JAM-B protein expression from mid- to late gestation in Balb/c-mated C57BL/6 females, which was absent in DBA/2J-mated Balb/c females. Due to the essential role of progesterone during gestation, we further assessed a possible modulation of JAM-B in mid-gestational placentae deficient in the progesterone receptor (Pgr(-/-)) and observed an increased expression of JAM-B in Pgr(-/-) placentae, compared to Pgr(+/+) tissue samples. We propose that JAM-B is an as yet underappreciated trophoblast lineage-specific protein, which is modulated via the progesterone receptor and shows unique strain-specific kinetics. Future work is needed to elucidate its possible contribution to placental processes necessary to ensuring its integrity, ultimately facilitating placental development and fetal growth.

  11. Use of additives to enhance the properties of cottonseed protein as wood adhesives

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Soy protein is currently being used commercially as a “green” wood adhesive. Previous work in this laboratory has shown that cottonseed protein isolate, tested on maple wood veneer, produced higher adhesive strength and hot water resistance relative to soy protein. In the present study, cottonseed...

  12. Extracellular proteins from Lactobacillus plantarum BMCM12 prevent adhesion of enteropathogens to mucin.

    PubMed

    Sánchez, Borja; Urdaci, María C

    2012-06-01

    The aim of this study was to study the interference of the extracellular proteins produced by Lactobacillus plantarum BMCM12 with the adhesion of some well-known gut pathogens. The extracellular proteins secreted by L. plantarum BMCM12 in MRS broth were precipitated, resolved by SDS-PAGE, and identified by tandem mass spectrometry. Discordances between the observed and the theoretical molecular masses of several proteins suggested the presence of protein glycosylation, corroborated with specific glycoprotein staining after protein de-glycosylation using trifluoromethanesulfonic acid. Experiments of exclusion, competition, or prevention of the pathogen adhesion to mucin were performed using BMCM12 extracellular proteins, using Escherichia coli LMG2092 and Salmonella enterica subsp. enterica LMG15860. Extracellular proteins from BMCM12 reduced significantly the adhesion of the pathogens when they were added prior to adhesion assays. These proteins play thus important roles in preventing pathogen adhesion to the mucin layer.

  13. Amigo Adhesion Protein Regulates Development of Neural Circuits in Zebrafish Brain*

    PubMed Central

    Zhao, Xiang; Kuja-Panula, Juha; Sundvik, Maria; Chen, Yu-Chia; Aho, Vilma; Peltola, Marjaana A.; Porkka-Heiskanen, Tarja; Panula, Pertti; Rauvala, Heikki

    2014-01-01

    The Amigo protein family consists of three transmembrane proteins characterized by six leucine-rich repeat domains and one immunoglobulin-like domain in their extracellular moieties. Previous in vitro studies have suggested a role as homophilic adhesion molecules in brain neurons, but the in vivo functions remain unknown. Here we have cloned all three zebrafish amigos and show that amigo1 is the predominant family member expressed during nervous system development in zebrafish. Knockdown of amigo1 expression using morpholino oligonucleotides impairs the formation of fasciculated tracts in early fiber scaffolds of brain. A similar defect in fiber tract development is caused by mRNA-mediated expression of the Amigo1 ectodomain that inhibits adhesion mediated by the full-length protein. Analysis of differentiated neural circuits reveals defects in the catecholaminergic system. At the behavioral level, the disturbed formation of neural circuitry is reflected in enhanced locomotor activity and in the inability of the larvae to perform normal escape responses. We suggest that Amigo1 is essential for the development of neural circuits of zebrafish, where its mechanism involves homophilic interactions within the developing fiber tracts and regulation of the Kv2.1 potassium channel to form functional neural circuitry that controls locomotion. PMID:24904058

  14. Amigo adhesion protein regulates development of neural circuits in zebrafish brain.

    PubMed

    Zhao, Xiang; Kuja-Panula, Juha; Sundvik, Maria; Chen, Yu-Chia; Aho, Vilma; Peltola, Marjaana A; Porkka-Heiskanen, Tarja; Panula, Pertti; Rauvala, Heikki

    2014-07-18

    The Amigo protein family consists of three transmembrane proteins characterized by six leucine-rich repeat domains and one immunoglobulin-like domain in their extracellular moieties. Previous in vitro studies have suggested a role as homophilic adhesion molecules in brain neurons, but the in vivo functions remain unknown. Here we have cloned all three zebrafish amigos and show that amigo1 is the predominant family member expressed during nervous system development in zebrafish. Knockdown of amigo1 expression using morpholino oligonucleotides impairs the formation of fasciculated tracts in early fiber scaffolds of brain. A similar defect in fiber tract development is caused by mRNA-mediated expression of the Amigo1 ectodomain that inhibits adhesion mediated by the full-length protein. Analysis of differentiated neural circuits reveals defects in the catecholaminergic system. At the behavioral level, the disturbed formation of neural circuitry is reflected in enhanced locomotor activity and in the inability of the larvae to perform normal escape responses. We suggest that Amigo1 is essential for the development of neural circuits of zebrafish, where its mechanism involves homophilic interactions within the developing fiber tracts and regulation of the Kv2.1 potassium channel to form functional neural circuitry that controls locomotion.

  15. Leptospira Protein Expression During Infection

    Technology Transfer Automated Retrieval System (TEKTRAN)

    We are characterizing protein expression in vivo during experimental leptospirosis using immunofluorescence microscopy. Coding regions for several proteins were identified through analysis of Leptospira interrogans serovar Copenhageni and L. borgpetersenii serovar Hardjo genomes. In addition, codi...

  16. Expression of claudins, occludin, junction adhesion molecule A and zona occludens 1 in canine organs

    PubMed Central

    Ahn, Changhwan; Shin, Da-Hye; Lee, Dongoh; Kang, Su-Myung; Seok, Ju-Hyung; Kang, Hee Young; Jeung, Eui-Bae

    2016-01-01

    Tight junctions are the outermost structures of intercellular junctions and are classified as transmembrane proteins. These factors form selective permeability barriers between cells, act as paracellular transporters and regulate structural and functional polarity of cells. Although tight junctions have been previously studied, comparison of the transcriptional-translational levels of these molecules in canine organs remains to be investigated. In the present study, organ-specific expression of the tight junction proteins, claudin, occludin, junction adhesion molecule A and zona occludens 1 was examined in the canine duodenum, lung, liver and kidney. Results of immunohistochemistry analysis demonstrated that the tight junctions were localized in intestinal villi and glands of the duodenum, bronchiolar epithelia and alveolar walls of the lung, endometrium and myometrium of the hepatocytes, and the distal tubules and glomeruli of the kidney. These results suggest that tight junctions are differently expressed in organs, and therefore may be involved in organ-specific functions to maintain physiological homeostasis. PMID:27600198

  17. Boronate Complex Formation with Dopa Containing Mussel Adhesive Protein Retards pH-Induced Oxidation and Enables Adhesion to Mica

    PubMed Central

    Israelachvili, Jacob N.; Chen, Yunfei; Waite, J. Herbert

    2014-01-01

    The biochemistry of mussel adhesion has inspired the design of surface primers, adhesives, coatings and gels for technological applications. These mussel-inspired systems often focus on incorporating the amino acid 3,4-dihydroxyphenyl-L-alanine (Dopa) or a catecholic analog into a polymer. Unfortunately, effective use of Dopa is compromised by its susceptibility to auto-oxidation at neutral pH. Oxidation can lead to loss of adhesive function and undesired covalent cross-linking. Mussel foot protein 5 (Mfp-5), which contains ∼30 mole % Dopa, is a superb adhesive under reducing conditions but becomes nonadhesive after pH-induced oxidation. Here we report that the bidentate complexation of borate by Dopa to form a catecholato-boronate can be exploited to retard oxidation. Although exposure of Mfp-5 to neutral pH typically oxidizes Dopa, resulting in a>95% decrease in adhesion, inclusion of borate retards oxidation at the same pH. Remarkably, this Dopa-boronate complex dissociates upon contact with mica to allow for a reversible Dopa-mediated adhesion. The borate protection strategy allows for Dopa redox stability and maintained adhesive function in an otherwise oxidizing environment. PMID:25303409

  18. ΔNp63α Transcriptionally Regulates the Expression of CTEN That Is Associated with Prostate Cell Adhesion

    PubMed Central

    Chen, Ya-Chi; Lo, Su Hao; Liao, Yi-Chun

    2016-01-01

    p63 is a member of the p53 transcription factor family and a linchpin of epithelial development and homeostasis. p63 drives the expression of many target genes involved in cell survival, adhesion, migration and cancer. In this study, we identify C-terminal tensin-like (CTEN) molecule as a downstream target of ΔNp63α, the predominant p63 isoform expressed in epithelium. CTEN belongs to the tensin family and is mainly localized to focal adhesions, which mediate many biological events such as cell adhesion, migration, proliferation and gene expression. Our study demonstrate that ΔNp63 and CTEN are both highly expressed in normal prostate epithelial cells and are down-regulated in prostate cancer. In addition, reduced expression of CTEN and ΔNp63 is correlated with prostate cancer progression from primary tumors to metastatic lesions. Silencing of ΔNp63 leads to decreased mRNA and protein levels of CTEN. ΔNp63α induces transcriptional activity of the CTEN promoter and a 140-bp fragment upstream of the transcription initiation site is the minimal promoter region required for activation. A putative binding site for p63 is located between -61 and -36 within the CTEN promoter and mutations of the critical nucleotides in this region abolish ΔNp63α-induced promoter activity. The direct interaction of ΔNp63α with the CTEN promoter was demonstrated using a chromatin immunoprecipitation (ChIP) assay. Moreover, impaired cell adhesion caused by ΔNp63α depletion is rescued by over-expression of CTEN, suggesting that CTEN is a downstream effector of ΔNp63α-mediated cell adhesion. In summary, our findings demonstrate that ΔNp63α functions as a trans-activation factor of CTEN promoter and regulates cell adhesion through modulating CTEN. Our study further contributes to the potential regulatory mechanisms of CTEN in prostate cancer progression. PMID:26784942

  19. B-cell receptor-associated protein 31 regulates human embryonic stem cell adhesion, stemness, and survival via control of epithelial cell adhesion molecule.

    PubMed

    Kim, Won-Tae; Seo Choi, Hong; Min Lee, Hyun; Jang, Young-Joo; Ryu, Chun Jeih

    2014-10-01

    B-Cell receptor-associated protein 31 (BAP31) regulates the export of secreted membrane proteins from the endoplasmic reticulum (ER) to the downstream secretory pathway. Previously, we generated a monoclonal antibody 297-D4 against the surface molecule on undifferentiated human embryonic stem cells (hESCs). Here, we found that 297-D4 antigen was localized to pluripotent hESCs and downregulated during early differentiation of hESCs and identified that the antigen target of 297-D4 was BAP31 on the hESC-surface. To investigate the functional role of BAP31 in hESCs, BAP31 expression was knocked down by small interfering RNA. BAP31 depletion impaired hESC self-renewal and pluripotency and drove hESC differentiation into multicell lineages. BAP31 depletion hindered hESC proliferation by arresting cell cycle at G0/G1 phase and inducing caspase-independent cell death. Interestingly, BAP31 depletion reduced hESC adhesion to extracellular matrix (ECM). Analysis of cell surface molecules showed decreased expression of epithelial cell adhesion molecule (EpCAM) in BAP31-depleted hESCs, while ectopic expression of BAP31 elevated the expression of EpCAM. EpCAM depletion also reduced hESC adhesion to ECM, arrested cell cycle at G0/G1 phase and induced cell death, producing similar effects to those of BAP31 depletion. BAP31 and EpCAM were physically associated and colocalized at the ER and cell surface. Both BAP31 and EpCAM depletion decreased cyclin D1 and E expression and suppressed PI3K/Akt signaling, suggesting that BAP31 regulates hESC stemness and survival via control of EpCAM expression. These findings provide, for the first time, mechanistic insights into how BAP31 regulates hESC stemness and survival via control of EpCAM expression.

  20. Glioblastoma expression of vitronectin and the alpha v beta 3 integrin. Adhesion mechanism for transformed glial cells.

    PubMed Central

    Gladson, C L; Cheresh, D A

    1991-01-01

    Glioblastoma multiforme, the most malignant astroglial-derived tumor, grows as an adherent mass and locally invades normal brain. An examination of adult cerebral glioblastoma biopsy material for the expression of adhesive proteins that might potentiate adhesion and invasion demonstrated tumor cell-associated vitronectin (5/5). In contrast, vitronectin was not detected associated with glial cells in low grade astroglial tumors (0/4), reactive astrogliosis (0/4), or in normal adult cortex and cerebral white matter (0/5). Also, a wide variety of other adhesive ligands were absent from the glioblastoma tumor parenchyma. The alpha v beta 3 integrin was the only vitronectin receptor identified in glioblastoma tumors in situ, and was also not expressed on low grade astroglial-derived tumors, reactive astrogliosis, or on glia or neurons in normal adult cortex and cerebral white matter. In a cell attachment assay, cultured glioblastoma cells attached to the parenchyma of glioblastoma tumor cryostat sections at the sites of vitronectin expression, but failed to attach to normal brain. This adhesion was inhibited by antibodies directed against vitronectin, the alpha v beta 3 integrin, and with an Arg-Gly-Asp-containing peptide. These data provide evidence for a cell adhesion mechanism in glioblastoma tumors that might potentiate glioblastoma cell invasion of normal brain. Images PMID:1721625

  1. International Union of Basic and Clinical Pharmacology. XCIV. Adhesion G protein-coupled receptors.

    PubMed

    Hamann, Jörg; Aust, Gabriela; Araç, Demet; Engel, Felix B; Formstone, Caroline; Fredriksson, Robert; Hall, Randy A; Harty, Breanne L; Kirchhoff, Christiane; Knapp, Barbara; Krishnan, Arunkumar; Liebscher, Ines; Lin, Hsi-Hsien; Martinelli, David C; Monk, Kelly R; Peeters, Miriam C; Piao, Xianhua; Prömel, Simone; Schöneberg, Torsten; Schwartz, Thue W; Singer, Kathleen; Stacey, Martin; Ushkaryov, Yuri A; Vallon, Mario; Wolfrum, Uwe; Wright, Mathew W; Xu, Lei; Langenhan, Tobias; Schiöth, Helgi B

    2015-01-01

    The Adhesion family forms a large branch of the pharmacologically important superfamily of G protein-coupled receptors (GPCRs). As Adhesion GPCRs increasingly receive attention from a wide spectrum of biomedical fields, the Adhesion GPCR Consortium, together with the International Union of Basic and Clinical Pharmacology Committee on Receptor Nomenclature and Drug Classification, proposes a unified nomenclature for Adhesion GPCRs. The new names have ADGR as common dominator followed by a letter and a number to denote each subfamily and subtype, respectively. The new names, with old and alternative names within parentheses, are: ADGRA1 (GPR123), ADGRA2 (GPR124), ADGRA3 (GPR125), ADGRB1 (BAI1), ADGRB2 (BAI2), ADGRB3 (BAI3), ADGRC1 (CELSR1), ADGRC2 (CELSR2), ADGRC3 (CELSR3), ADGRD1 (GPR133), ADGRD2 (GPR144), ADGRE1 (EMR1, F4/80), ADGRE2 (EMR2), ADGRE3 (EMR3), ADGRE4 (EMR4), ADGRE5 (CD97), ADGRF1 (GPR110), ADGRF2 (GPR111), ADGRF3 (GPR113), ADGRF4 (GPR115), ADGRF5 (GPR116, Ig-Hepta), ADGRG1 (GPR56), ADGRG2 (GPR64, HE6), ADGRG3 (GPR97), ADGRG4 (GPR112), ADGRG5 (GPR114), ADGRG6 (GPR126), ADGRG7 (GPR128), ADGRL1 (latrophilin-1, CIRL-1, CL1), ADGRL2 (latrophilin-2, CIRL-2, CL2), ADGRL3 (latrophilin-3, CIRL-3, CL3), ADGRL4 (ELTD1, ETL), and ADGRV1 (VLGR1, GPR98). This review covers all major biologic aspects of Adhesion GPCRs, including evolutionary origins, interaction partners, signaling, expression, physiologic functions, and therapeutic potential.

  2. Control of islet intercellular adhesion molecule-1 expression by interferon-alpha and hypoxia.

    PubMed

    Chakrabarti, D; Huang, X; Beck, J; Henrich, J; McFarland, N; James, R F; Stewart, T A

    1996-10-01

    The ability of interferon-alpha (IFN-alpha) to induce the adhesion molecules that characterize the islets of patients with type I diabetes has been investigated. We have found that all tested recombinant IFN-as will induce major histocompatibility complex (MHC) class I on arterial endothelial cells. Some but not all IFN-as will induce intercellular adhesion molecule-1 (ICAM-1). However, there is only a transient and modest increase in VCAM on arterial endothelial cells. IFN-alpha has very little effect on endothelial MHC class II expression but will induce these proteins on monocytes. Thus, there is a close concordance between the biological actions of IFN-alpha and the appearance of those adhesion molecules induced in the islets of patients with type I diabetes. IFN-alpha is also produced in normal human islets during short-term cultures, probably as a result of the ischemia present at the center of the islet. This induction of IFN-alpha by hypoxia may explain the previously reported spontaneous induction of ICAM-1 in human islets and may also be a contributing factor to the failure of islet grafts.

  3. Activation of cyclic amp/protein kinase: a signaling pathway enhances osteoblast cell adhesion on biomaterials for regenerative engineering.

    PubMed

    Lo, Kevin W-H; Ashe, Keshia M; Kan, Ho Man; Lee, Duron A; Laurencin, Cato T

    2011-04-01

    Osteoblast cell adhesion on biomaterials is an important goal for implants to be useful in bone regeneration technologies. The adhesion of osteoblastic cells to biomaterials has been investigated in the field of bone regenerative engineering. Previous work from our group demonstrated that osteoblastic cells adhering to biodegradable biomaterials require the expression of integrins on the cell surface. However, the underlying molecular signaling mechanism is still not fully clear. We report here that cyclic adenosine monophosphate (cAMP), a small signaling molecule, regulates osteoblast cell adhesion to biomaterial surfaces. We used an in vitro cell adhesion assay to demonstrate that at 0.1 mM, 8-Br-cAMP, a cell-permeable cAMP analog, significantly enhances osteoblast-like cells' (MC3T3-E1) adherence to biomaterials. Moreover, we demonstrate that a commonly used cAMP-elevating agent, forskolin, promotes cell adhesion similar to that of the cell permeable cAMP analog. By using different target-specific cAMP analogs: 8-CPT-2Me-cAMP which specifically activates exchange protein activated by cAMP (Epac), and 6-Bnz-cAMP which specifically activates protein kinase A (PKA), we observed that the PKA signaling pathway plays a dominant role in this process. Thus, this report suggests a new method to enhance osteoblast cell adhesion on biodegradable biomaterials for bone regenerative engineering applications.

  4. Protein-based underwater adhesives and the prospects for their biotechnological production

    PubMed Central

    Stewart, Russell J.

    2011-01-01

    Biotechnological approaches to practical production of biological protein-based adhesives have had limited success over the last several decades. Broader efforts to produce recombinant adhesive proteins may have been limited by early disappointments. More recent synthetic polymer approaches have successfully replicated some aspects of natural underwater adhesives. For example, synthetic polymers, inspired by mussels, containing the catecholic functional group of 3,4-L-dihydroxyphenylalanine adhere strongly to wet metal oxide surfaces. Synthetic complex coacervates inspired by the Sandcastle worm are water-borne adhesives that can be delivered underwater without dispersing. Synthetic approaches offer several advantages, including versatile chemistries and scalable production. In the future, more sophisticated mimetic adhesives may combine synthetic copolymers with recombinant or agriculture-derived proteins to better replicate the structural and functional organization of natural adhesives. PMID:20890598

  5. Protein-based underwater adhesives and the prospects for their biotechnological production.

    PubMed

    Stewart, Russell J

    2011-01-01

    Biotechnological approaches to practical production of biological protein-based adhesives have had limited success over the last several decades. Broader efforts to produce recombinant adhesive proteins may have been limited by early disappointments. More recent synthetic polymer approaches have successfully replicated some aspects of natural underwater adhesives. For example, synthetic polymers, inspired by mussels, containing the catecholic functional group of 3,4-L-dihydroxyphenylalanine adhere strongly to wet metal oxide surfaces. Synthetic complex coacervates inspired by the Sandcastle worm are water-borne adhesives that can be delivered underwater without dispersing. Synthetic approaches offer several advantages, including versatile chemistries and scalable production. In the future, more sophisticated mimetic adhesives may combine synthetic copolymers with recombinant or agriculture-derived proteins to better replicate the structural and functional organization of natural adhesives.

  6. Onion yellow phytoplasma P38 protein plays a role in adhesion to the hosts.

    PubMed

    Neriya, Yutaro; Maejima, Kensaku; Nijo, Takamichi; Tomomitsu, Tatsuya; Yusa, Akira; Himeno, Misako; Netsu, Osamu; Hamamoto, Hiroshi; Oshima, Kenro; Namba, Shigetou

    2014-12-01

    Adhesins are microbial surface proteins that mediate the adherence of microbial pathogens to host cell surfaces. In Mollicutes, several adhesins have been reported in mycoplasmas and spiroplasmas. Adhesins P40 of Mycoplasma agalactiae and P89 of Spiroplasma citri contain a conserved amino acid sequence known as the Mollicutes adhesin motif (MAM), whose function in the host cell adhesion remains unclear. Here, we show that phytoplasmas, which are plant-pathogenic mollicutes transmitted by insect vectors, possess an adhesion-containing MAM that was identified in a putative membrane protein, PAM289 (P38), of the 'Candidatus Phytoplasma asteris,' OY strain. P38 homologs and their MAMs were highly conserved in related phytoplasma strains. While P38 protein was expressed in OY-infected insect and plant hosts, binding assays showed that P38 interacts with insect extract, and weakly with plant extract. Interestingly, the interaction of P38 with the insect extract depended on MAM. These results suggest that P38 is a phytoplasma adhesin that interacts with the hosts. In addition, the MAM of adhesins is important for the interaction between P38 protein and hosts.

  7. Expression and purification of membrane proteins.

    PubMed

    Kubicek, Jan; Block, Helena; Maertens, Barbara; Spriestersbach, Anne; Labahn, Jörg

    2014-01-01

    Approximately 30% of a genome encodes for membrane proteins. They are one of the most important classes of proteins in that they can receive, differentiate, and transmit intra- and intercellular signals. Some examples of classes of membrane proteins include cell-adhesion molecules, translocases, and receptors in signaling pathways. Defects in membrane proteins may be involved in a number of serious disorders such as neurodegenerative diseases (e.g., Alzheimer's) and diabetes. Furthermore, membrane proteins provide natural entry and anchoring points for the molecular agents of infectious diseases. Thus, membrane proteins constitute ~50% of known and novel drug targets. Progress in this area is slowed by the requirement to develop methods and procedures for expression and isolation that are tailored to characteristic properties of membrane proteins. A set of standard protocols for the isolation of the targets in quantities that allow for the characterization of their individual properties for further optimization is required. The standard protocols given below represent a workable starting point. If optimization of yields is desired, a variation of conditions as outlined in the theory section is recommended.

  8. Recombinant protein expression in Nicotiana.

    PubMed

    Matoba, Nobuyuki; Davis, Keith R; Palmer, Kenneth E

    2011-01-01

    Recombinant protein pharmaceuticals are now widely used in treatment of chronic diseases, and several recombinant protein subunit vaccines are approved for human and veterinary use. With growing demand for complex protein pharmaceuticals, such as monoclonal antibodies, manufacturing capacity is becoming limited. There is increasing need for safe, scalable, and economical alternatives to mammalian cell culture-based manufacturing systems, which require substantial capital investment for new manufacturing facilities. Since a seminal paper reporting immunoglobulin expression in transgenic plants was published in 1989, there have been many technological advances in plant expression systems to the present time where production of proteins in leaf tissues of nonfood crops such as Nicotiana species is considered a viable alternative. In particular, transient expression systems derived from recombinant plant viral vectors offer opportunities for rapid expression screening, construct optimization, and expression scale-up. Extraction of recombinant proteins from Nicotiana leaf tissues can be achieved by collection of secreted protein fractions, or from a total protein extract after grinding the leaves with buffer. After separation from solids, the major purification challenge is contamination with elements of the photosynthetic complex, which can be solved by application of a variety of facile and proven strategies. In conclusion, the technologies required for safe, efficient, scalable manufacture of recombinant proteins in Nicotiana leaf tissues have matured to the point where several products have already been tested in phase I clinical trials and will soon be followed by a rich pipeline of recombinant vaccines, microbicides, and therapeutic proteins.

  9. Intercellular adhesion molecule-1 (ICAM-1) expression is upregulated in autoimmune murine lupus nephritis.

    PubMed Central

    Wuthrich, R. P.; Jevnikar, A. M.; Takei, F.; Glimcher, L. H.; Kelley, V. E.

    1990-01-01

    Intercellular adhesion molecule-1 (ICAM-1) is a cell-surface protein regulating interactions among immune cells. To determine whether altered expression of ICAM-1 occurs in autoimmune lupus nephritis, we studied ICAM-1 expression in kidneys of normal and autoimmune MRL-lpr and (NZBX NZW)F1 (NZB/W) mice. By immunoperoxidase staining, ICAM-1 is constitutively expressed at low levels in proximal tubules (PT), endothelium and interstitial cells in normal C3H/FeJ mice. In nephritic MRL-lpr and NZB/W kidneys, staining for ICAM-1 is increased in the PT, particularly in the brush border, and is prominent in the glomerular mesangium and the endothelium of large vessels. By Western blot analysis, ICAM-1 is not detected in the urine of normal BALB/c and C3H/FeJ or autoimmune MRL-lpr. By Northern blot analysis, nephritic MRL-lpr and NZB/W have a two- to fivefold increase in steady state levels of ICAM-1 transcripts in the kidney as compared with normal or prenephritic mice. This is paralleled by an increase in MHC class II transcripts. In cultured PT cells, ICAM-1 is expressed at basal levels in PT and is increased by the cytokines interferon-gamma, IL-1 alpha, and TNF-alpha. Thus cytokine-mediated upregulation of ICAM-1 in lupus nephritis may promote interaction of immune cells with renal tissue. The predominant apical expression of ICAM-1 opposite to the basolateral Ia expression suggests a novel role for this adhesion molecule in PT. Images Figure 1 Figure 2 Figure 3 Figure 6 Figure 7 PMID:1968316

  10. In vivo post-translational modifications of recombinant mussel adhesive protein in insect cells.

    PubMed

    Lim, Seonghye; Kim, Kyoung Ro; Choi, Yoo Seong; Kim, Dae-Kyum; Hwang, Daehee; Cha, Hyung Joon

    2011-01-01

    Mussel adhesive proteins (MAPs) have been suggested as promising bioadhesives for diverse application fields, including medical uses. Previously, we successfully constructed and produced a new type of functional recombinant MAP, fp-151, in a prokaryotic Escherichia coli expression system. Even though the E. coli-derived MAP showed several excellent features, such as high production yield and efficient purification, in vitro enzymatic modification is required to convert tyrosine residues to l-3,4-dihydroxyphenyl alanine (dopa) molecules for its adhesive ability, due to the intrinsic inability of E. coli to undergo post-translational modification. In this work, we produced a soluble recombinant MAP in insect Sf9 cells, which are widely used as an effective and convenient eukaryotic expression system for eukaryotic foreign proteins. Importantly, we found that insect-derived MAP contained converted dopa residues by in vivo post-translational modification. In addition, insect-derived MAP also had other post-translational modifications including phosphorylation of serine and hydroxylation of proline that originally occurred in some natural MAPs. To our knowledge, this is the first report on in vivo post-translational modifications of MAP containing dopa and other modified amino acid residues.

  11. MicroRNA-221 controls expression of intercellular adhesion molecule-1 in epithelial cells in response to Cryptosporidium parvum infection

    PubMed Central

    Gong, Ai-Yu; Hu, Guoku; Zhou, Rui; Liu, Jun; Feng, Yaoyu; Soukup, Garrett A.; Chen, Xian-Ming

    2011-01-01

    Cryptosporidium parvum is a protozoan parasite that infects gastrointestinal epithelial cells and causes diarrheal disease in humans and animals globally. Pathological changes following C. parvum infection include crypt hyperplasia, a modest inflammatory reaction with increased infiltration of lymphocytes into intestinal mucosa. Expression of adhesion molecules such as intercellular adhesion molecule-1 (ICAM-1), on infected epithelial cell surfaces may facilitate adhesion and recognition of lymphocytes at infection sites. MicroRNAs (miRNAs) are small RNA molecules of 23 nucleotides that negatively regulate protein-coding gene expression via translational suppression or mRNA degradation. We recently reported that microRNA-221 (miR-221) regulates ICAM-1 translation through targeting the ICAM-1 3′-untranslated region (UTR). In this study, we tested the role of miR-221 in regulating ICAM-1 expression in epithelial cells in response to C. parvum infection using an in vitro model of human biliary cryptosporidiosis. Up-regulation of ICAM-1 at both message and protein levels was detected in epithelial cells following C. parvum infection. Inhibition of ICAM-1 transcription with actinomycin D could only partially block C. parvum-induced ICAM-1 expression at the protein level. Cryptosporidium parvum infection decreased miR-221 expression in infected epithelial cells. When cells were transfected with a luciferase reporter construct covering the miR-221 binding site in the ICAM-1 3′-UTR and then exposed to C. parvum, an enhanced luciferase activity was detected. Transfection of miR-221 precursor abolished C. parvum-stimulated ICAM-1 protein expression. In addition, expression of ICAM-1 on infected epithelial cells facilitated epithelial adherence of co-cultured Jurkat cells. These results indicate that miR-221-mediated translational suppression controls ICAM-1 expression in epithelial cells in response to C. parvum infection. PMID:21236259

  12. C1q/TNF-related protein-9 inhibits cytokine-induced vascular inflammation and leukocyte adhesiveness via AMP-activated protein kinase activation in endothelial cells.

    PubMed

    Jung, Chang Hee; Lee, Min Jung; Kang, Yu Mi; Lee, Yoo La; Seol, So Mi; Yoon, Hae Kyeong; Kang, Sang-Wook; Lee, Woo Je; Park, Joong-Yeol

    2016-01-05

    Although recent studies have reported cardioprotective effects of C1q/TNF-related protein 9 (CTRP9), the closet adiponectin paralog, its role on cytokine-induced endothelial inflammation is unknown. We investigated whether CTRP9 prevented inflammatory cytokine-induced nuclear factor-kappa B (NF-κB) activation and inhibited the expression of adhesion molecules and a chemokine in the vascular endothelial cell. We used human aortic endothelial cells (HAECs) to examine the effects of CTRP9 on NF-κB activation and the expression of NF-κB-mediated genes, including intercellular adhesion molecule-1 (ICAM-1), vascular cell adhesion molecule-1 (VCAM-1), and monocyte chemoattractant protein-1 (MCP-1). Tumor necrosis factor alpha (TNFα) was used as a representative proinflammatory cytokine. In an adhesion assay using THP-1 cells, CTRP9 reduced TNFα-induced adhesion of monocytes to HAECs. Treatment with CTRP9 significantly decreased TNFα-induced activation of NF-κB, as well as the expression of ICAM-1, VCAM-1, and MCP-1. In addition, treatment with CTRP9 significantly increased the phosphorylation of AMP-activated protein kinase (AMPK) and acetyl-CoA carboxylase (ACC), the downstream target of AMPK. The inhibitory effect of CTRP9 on the expression of ICAM-1, VCAM-1, and MCP-1 and monocyte adhesion to HAECs was abolished after transfection with an AMPKα1-specific siRNA. Our study is the first to demonstrate that CTRP9 attenuates cytokine-induced vascular inflammation in endothelial cells mediated by AMPK activation.

  13. Berberine reduces leukocyte adhesion to LPS-stimulated endothelial cells and VCAM-1 expression both in vivo and in vitro.

    PubMed

    Wu, Y-H; Chuang, S-Y; Hong, W-C; Lai, Y-J; Chang, G-J; Pang, J-H S

    2012-01-01

    Leukocyte adhesion to endothelium plays a critical initiating role in inflammation. Berberine, an anti-inflammatory natural compound, is known to attenuate lipopolysaccharide (LPS)-induced lung injury and improve survival of endotoxemic animals with mechanism not fully clarified. This study investigated the effects of berberine on the LPS-induced leukocyte-endothelial cell adhesion both in vivo and in vitro. We first established an animal model to observe the in vivo LPS-induced adhesion of leukocytes to the endothelium of venules in the lung tissue dose-dependently. Pretreatment of LPS-stimulated rats with berberine for 1 h reduced the leukocyte-endothelium adhesion and vascular cell adhesion molecule-1 (VCAM-1) expression in lung. Pretreatment of LPS-stimulated vascular endothelial cells with berberine also dose-dependently decreased the number of adhered THP-1 cells and VCAM-1 expression at both RNA and protein levels. Berberine was further confirmed to inhibit the nuclear translocation and DNA binding activity of LPS-activated nuclear factor-kappa B (NF-kappa B). These data demonstrated an additional molecular mechanism for the profound anti-inflammatory effect of berberine.

  14. Processing of mussel adhesive protein analog thin films by matrix assisted pulsed laser evaporation

    NASA Astrophysics Data System (ADS)

    Cristescu, R.; Patz, T.; Narayan, R. J.; Menegazzo, N.; Mizaikoff, B.; Mihaiescu, D. E.; Messersmith, P. B.; Stamatin, I.; Mihailescu, I. N.; Chrisey, D. B.

    2005-07-01

    Mussel adhesive proteins are a new class of biologically-derived materials that possess unique biocompatibility, bioactivity, and adhesion properties. We have demonstrated successful thin film growth of 3,4-dihydroxyphenyl- L-alanine modified poly(ethylene oxide)-poly(propylene oxide)-poly(ethylene oxide) (DOPA modified- PEO-PPO-PEO) block copolymer, a mussel adhesive protein analog, using matrix assisted pulsed laser evaporation. We have demonstrated that the main functional groups of the mussel adhesive protein analog are present in the transferred film. The effect of increasing of chain length of the mussel adhesive protein analog on film structure was also examined. These novel polymer thin films could have numerous medical and technological applications if their thin film properties are similar to what is found in bulk. This is the first report of successful MAPLE deposition of this material as thin films.

  15. Usefulness of epithelial cell adhesion molecule expression in the algorithmic approach to Lynch syndrome identification.

    PubMed

    Musulen, Eva; Blanco, Ignacio; Carrato, Cristina; Fernandez-Figueras, Maria Teresa; Pineda, Marta; Capella, Gabriel; Ariza, Aurelio

    2013-03-01

    Lynch syndrome (LS), the most frequent form of hereditary colorectal cancer syndrome, is caused by germ-line mutations in the mismatch repair system genes. Recently, a new mechanism involving the epithelial cell adhesion molecule (EPCAM)/TACSTD1 gene has been shown to be responsible in cases with abnormal MSH2 expression. Of interest, 3' exons deletions of the EPCAM gene, which is located upstream of MSH2 in chromosome 2, are associated with MSH2 promoter hypermethylation. EPCAM protein, expressed in epithelial tissues, is encoded by the EPCAM/TACSTD1 gene. Our study's aim was to explore EPCAM expression in colorectal carcinomas of MSH2-associated LS cases to evaluate the usefulness of EPCAM protein expression in the algorithm approach to LS population screening. We included a total of 19 MSH2-negative colorectal carcinomas from 14 different patients in whom we were able to perform a complete germ-line analysis. Nine patients showed a deleterious germ-line mutation that involved the MSH2 gene in 3 instances and the EPCAM gene exon 9 in 6 instances. All patients harboring the EPCAM mutation belonged to the same family. Of the 19 colorectal carcinomas, EPCAM expression loss was seen in only 5 tumors, all of them from patients showing a germ-line EPCAM deletion. Of interest, 6 tumors from 3 different patients carrying the same germ-line EPCAM deletion showed normal EPCAM expression. In conclusion, owing to the high specificity of EPCAM protein expression to identify LS patients carrying an EPCAM deletion, we recommend adding EPCAM immunohistochemistry to the LS diagnostic algorithm in MSH2-negative colorectal carcinoma.

  16. A mutant form of the rho protein can restore stress fibers and adhesion plaques in v-src transformed fibroblasts.

    PubMed

    Mayer, T; Meyer, M; Janning, A; Schiedel, A C; Barnekow, A

    1999-03-25

    The organization of polymerized actin in the mammalian cell is regulated by several members of the rho family. Three rho proteins, cdc42, rac and rho act in a cascade to organize the intracellular actin cytoskeleton. Rho proteins are involved in the formation of actin stress fibers and adhesion plaques in fibroblasts. During transformation of mammalian cells by oncogenes the cytoskeleton is rearranged and stress fibers and adhesion plaques are disintegrated. In this paper we investigate the function of the rho protein in RR1022 rat fibroblasts transformed by the Rous sarcoma virus. Two activated mutants of the rho protein, rho G14V and rho Q63L, and a dominant negative mutant, rho N1171, were stably transfected into RR1022 cells. The resulting cell lines were analysed for the organization of polymerized actin and adhesion plaques. Cells expressing rho Q63L, but not rho wt, rho G14V or rho N1171, showed an altered morphology. These cells displayed a flat, fibroblast like shape when compared with the RR1022 ancestor cells. Immunofluorescence analyses revealed that actin stress fibers and adhesion plaques were rearranged in these cells. We conclude from these data that an active rho protein can restore elements of the actin cytoskeleton in transformed cells by overriding the tyrosine kinase phosphorylation induced by the pp60(v-src).

  17. Role of glucocorticoids in neutrophil and endothelial adhesion molecule expression and function

    PubMed Central

    Talbot, Vivienne

    1992-01-01

    Glucocorticoids are very effective inhibitors of both the acute and chronic inflammatory response. In this study the hypothesis that glucocorticoids inhibit an early component of the inflammatory response, neutrophil adhesion to endothelium, by down-regulation of adhesion molecules on neutrophils or endothelium was examined. No effect of dexamethasone on neutrophil adhesion to endothelium or of antigen expression by neutrophils or endothelium was found. The mechanism of action of glucocorticoids in the inflammatory response is probably not mediated by alterations in adhesion molecules. PMID:18475448

  18. Adhesion G-protein-coupled receptors: elusive hybrids come of age.

    PubMed

    Simundza, Julia; Cowin, Pamela

    2013-12-01

    Adhesion G-protein-coupled receptors (GPCRs) are the most recently identified and least understood subfamily of GPCRs. Adhesion GPCRs are characterized by unusually long ectodomains with adhesion-related repeats that facilitate cell- cell and cell-cell matrix contact, as well as a proteolytic cleavage site-containing domain that is a structural hallmark of the family. Their unusual chimeric structure of adhesion-related ectodomain with a seven-pass transmembrane domain and cytoplasmic signaling makes these proteins highly versatile in mediating cellular signaling in response to extracellular adhesion or cell motility events. The ligand binding and cytoplasmic signaling modes for members of this family are beginning to be elucidated, and recent studies have demonstrated critical roles for Adhesion GPCRs in planar polarity and other important cell-cell and cell-matrix interactions during development and morphogenesis, as well as heritable diseases and cancer.

  19. PRIMING EFFECT OF HOMOCYSTEINE ON INDUCIBLE VASCULAR CELL ADHESION MOLECULE-1 EXPRESSION IN ENDOTHELIAL CELLS

    PubMed Central

    Séguin, Chantal; Abid, Md. Ruhul; Spokes, Katherine C.; Schoots, Ivo G; Brkovic, Alexandre; Sirois, Martin G.; Aird, William C.

    2017-01-01

    Hyperhomocysteinemia is an independent risk factor for the development of atherosclerosis, as well as for arterial and venous thrombosis. However, the mechanisms through which elevated circulating levels of homocysteine cause vascular injury and promote thrombosis remain unclear. Here, we tested the hypothesis that homocysteine (Hcy) sensitizes endothelial cells to the effect of inflammatory mediators. Human umbilical vein endothelial cells (HUVEC) were incubated with Hcy 1.0 mM for varying time points, and then treated in the absence or presence of 1.5 U/ml thrombin or 10 ng/ml lipopolysaccharide (LPS). Hcy alone had no effect on the expression of vascular cell adhesion molecule (VCAM)-1. However, Hcy enhanced thrombin- and LPS-mediated induction of VCAM-1 mRNA and protein levels. Consistent with these results, pretreatment of HUVEC with Hcy resulted in a two-fold increase in LSP-mediated induction of leukocyte adhesion. The latter effect was significantly inhibited by anti-VCAM-1 antibodies. Together, these findings suggest that Hcy sensitizes HUVEC to the effect of inflammatory mediators thrombin and LPS, at least in part through VCAM-1 expression and function. PMID:18406566

  20. Overexpressed Ly-6A.2 mediates cell-cell adhesion by binding a ligand expressed on lymphoid cells.

    PubMed Central

    Bamezai, A; Rock, K L

    1995-01-01

    The Ly-6 locus encodes several cell surface proteins whose functions are unknown. Although it is hypothesized that these proteins may be receptors, there is no direct evidence that they bind a ligand. Herein we present evidence that Ly-6A.2, a Ly-6 protein expressed on T lymphocytes, binds a ligand expressed on normal thymocytes and splenic B and T cells. We find that transgenic thymocytes that overexpress Ly-6A.2 spontaneously aggregate in culture. This homotypic adhesion requires the overexpression of Ly-6A.2 because it is not observed in cultures of nontransgenic thymocytes. The aggregation of Ly-6A.2 transgenic thymocytes is inhibited by phosphatidylinositol-specific phospholipase C (which removes Ly-6A.2 and other glycosylphosphatidylinositol-anchored proteins from the membrane). Some anti-Ly-6A.2 monoclonal antibodies, including nonactivating ones and Fab' fragments, inhibit this aggregation. In contrast, other anti-Ly-6A.2 monoclonal antibodies increase the aggregation of transgenic but not nontransgenic thymocytes. To further examine whether Ly-6A.2 mediates adhesion (versus inducing another adhesion pathway) reaggregation assays were performed with paraformaldehyde-fixed Tg+ thymocytes. Paraformaldehyde-fixed Tg+ thymocytes reaggregate in culture and this aggregation is also blocked by phosphatidyl-inositol-specific phospholipase C and anti-Ly-6A.2 monoclonal antibodies. These results indicate that the homotypic adhesion of cultured Ly-6A.2 transgenic thymocytes is directly mediated by Ly-6A.2 and, more importantly, strongly suggests that Ly-6A.2 binds a ligand that is expressed on thymocytes. Tg+ thymocytes also bind to nontransgenic thymocytes, B cells, and T cells, indicating that normal cells naturally express the Ly-6A.2 ligand. Images Fig. 1 Fig. 2 PMID:7753800

  1. Biomimetic soy protein nanocomposites with calcium carbonate crystalline arrays for use as wood adhesive.

    PubMed

    Liu, Dagang; Chen, Huihuang; Chang, Peter R; Wu, Qinglin; Li, Kaifu; Guan, Litao

    2010-08-01

    Despite the biodegradability, non-toxicity, and renewability, commercially available soy protein-based adhesives still have not been widely adopted by industry, partially due to their disappointing performances, i.e., low glue strength in the dry state and no glue strength in the wet state. In this study, biomimetic soy protein/CaCO(3) hybrid wood glue was devised and an attempt made to improve the adhesion strength. The structure and morphology of the adhesive and its fracture bonding interface and adhesion strength were investigated. Results showed that the compact rivets or interlocking links, and ion crosslinking of calcium, carbonate, hydroxyl ions in the adhesive greatly improving the water-resistance and bonding strength of soy protein adhesives. Glue strength of soy protein hybrid adhesive was higher than 6 MPa even after three water-immersion cycles. This green and sustainable proteinous hybrid adhesive, with high glue strength and good water-resistance, is a good substitute for formaldehyde wood glues.

  2. Proper Control of Caulobacter crescentus Cell Surface Adhesion Requires the General Protein Chaperone DnaK

    PubMed Central

    Eaton, Daniel S.; Crosson, Sean

    2016-01-01

    ABSTRACT Growth in a surface-attached bacterial community, or biofilm, confers a number of advantages. However, as a biofilm matures, high-density growth imposes stresses on individual cells, and it can become less advantageous for progeny to remain in the community. Thus, bacteria employ a variety of mechanisms to control attachment to and dispersal from surfaces in response to the state of the environment. The freshwater oligotroph Caulobacter crescentus can elaborate a polysaccharide-rich polar organelle, known as the holdfast, which enables permanent surface attachment. Holdfast development is strongly inhibited by the small protein HfiA; mechanisms that control HfiA levels in the cell are not well understood. We have discovered a connection between the essential general protein chaperone, DnaK, and control of C. crescentus holdfast development. C. crescentus mutants partially or completely lacking the C-terminal substrate binding “lid” domain of DnaK exhibit enhanced bulk surface attachment. Partial or complete truncation of the DnaK lid domain increases the probability that any single cell will develop a holdfast by 3- to 10-fold. These results are consistent with the observation that steady-state levels of an HfiA fusion protein are significantly diminished in strains that lack the entire lid domain of DnaK. While dispensable for growth, the lid domain of C. crescentus DnaK is required for proper chaperone function, as evidenced by observed dysregulation of HfiA and holdfast development in strains expressing lidless DnaK mutants. We conclude that DnaK is an important molecular determinant of HfiA stability and surface adhesion control. IMPORTANCE Regulatory control of cell adhesion ensures that bacterial cells can transition between free-living and surface-attached states. We define a role for the essential protein chaperone, DnaK, in the control of Caulobacter crescentus cell adhesion. C. crescentus surface adhesion is mediated by an envelope

  3. Immunolocalization of specific keratin associated beta-proteins (beta-keratins) in the adhesive setae of Gekko gecko.

    PubMed

    Alibardi, Lorenzo

    2013-08-01

    The previous identification of 21 proteins in the digital setae transcriptome of Gekko gecko, 2 alpha-keratins of 52-53kDa and 19 beta-proteins (beta-keratins) of 10-21kDa, has indicated that most of setal corneous proteins are cysteine-rich. The production of specific antibodies for two of the main beta-protein subfamilies expressed in gecko setae has allowed the ultrastructural localization of two beta-proteins indicated as Ge-cprp-9 (cysteine-rich) and Ge-gprp-6 (glycine-rich). Only Ge-cprp-9, representing most of the 16 cysteine-rich beta-proteins, is present in the oberhautchen, setae and in the terminal spatula where adhesion takes place, supporting the previous expression study. Instead, the glycine-rich beta-proteins (Ge-gprp-6), representing the 3 glycine-rich beta-proteins of digital epidermis is only present in the stiff beta-layer of the digital scales and in the thin beta layer of the pad lamella sustaining the setae. Ge-cprp-9 is representative for most of the remaining 15 cys-rich proteins (Ge-cprp 1-16) and may have a structural and functional role in the process of adhesion. Most of the cysteine-rich setal proteins have a net positive charge and it is here hypothesized that these proteins may induce the formation of dipoles at the surface interface between the spatula and the substrate, enhancing the van der Waals forces and therefore adhesion to the substrate. The selection and improvement of these proteins during the evolution of geckos may have represented a successful factor for the survival and ecological adaptations of these climbing lizards.

  4. Lectin I from Bauhinia variegata (BVL-I) expressed by Pichia pastoris inhibits initial adhesion of oral bacteria in vitro.

    PubMed

    Klafke, Gabriel Baracy; Moreira, Gustavo Marçal Schmidt Garcia; Pereira, Juliano Lacava; Oliveira, Patrícia Diaz; Conceição, Fabricio Rochedo; Lund, Rafael Guerra; Grassmann, André Alex; Dellagostin, Odir Antonio; da Silva Pinto, Luciano

    2016-12-01

    Lectins are non-immune proteins that reversibly bind to carbohydrates in a specific manner. Bauhinia variegata lectin I (BVL-I) is a Gal/GalNAc-specific, single-chain lectin isolated from Bauhinia variegata seeds that has been implicated in the inhibition of bacterial adhesion and the healing of damaged skin. Since the source of the native protein (nBVL) is limited, this study aimed to produce recombinant BVL-I in Pichia pastoris (rBVL-Ip). The coding sequence for BVL-I containing preferential codons for P. pastoris was cloned into the pPICZαB plasmid. A single expressing clone was selected and fermented, resulting in the secretion and glycosylation of the protein. Fed-batch fermentation in 7L-scale was performed, and the recombinant lectin was purified from culture supernatant, resulting in a yield of 1.5mg/L culture. Further, rBVL-Ip was compared to nBVL and its recombinant version expressed in Escherichia coli BL21 (DE3) (rBVL-Ie). Although it was expressed as a monomer, rBVL-Ip retained its biological activity since it was able to impair the initial adhesion of Streptococcus mutans and S. sanguinis in an in vitro model of biofilm formation and bacterial adhesion. In summary, rBVL-Ip produced in Pichia pastoris represents a viable alternative to large-scale production, encouraging further biological application studies with this lectin.

  5. Ascorbate inhibits platelet-endothelial adhesion in an in-vitro model of sepsis via reduced endothelial surface P-selectin expression.

    PubMed

    Secor, Dan; Swarbreck, Scott; Ellis, Christopher G; Sharpe, Michael D; Feng, Qingping; Tyml, Karel

    2017-01-01

    Plugging of the capillary bed can lead to organ failure and mortality in sepsis. We have reported that intravenous ascorbate injection reduces platelet adhesion to the capillary wall and capillary plugging in septic mice. Both platelet adhesion and capillary plugging require P-selectin, a key adhesion molecule. To elucidate the beneficial effect of ascorbate, we hypothesized that ascorbate reduces platelet-endothelial adhesion by reducing P-selectin surface expression in endothelial cells. We used mouse platelets, and monolayers of cultured microvascular endothelial cells (mouse skeletal muscle origin) stimulated with lipopolysaccharide, to examine platelet-endothelial adhesion. P-selectin mRNA expression in endothelial cells was determined by real-time PCR and P-selectin protein expression at the surface of these cells by immunofluorescence. Secretion of von Willebrand factor from cells into the supernatant (a measure of P-selectin-containing granule exocytosis) was determined by ELISA. Lipopolysaccharide (10 μg/ml, 1 h) increased platelet-endothelial adhesion. P-selectin-blocking antibody inhibited this adhesion. Lipopolysaccharide also increased P-selectin mRNA in endothelial cells, P-selectin expression at the endothelial surface, and von Willebrand factor secretion. Ascorbate pretreatment (100 μmol/l, 4 h) inhibited the increased platelet adhesion, surface expression of P-selectin, and von Willebrand factor secretion, but not the increase in P-selectin mRNA. The lipopolysaccharide-induced increase in platelet-endothelial adhesion requires P-selectin presence at the endothelial surface. Ascorbate's ability to reduce this presence could be important in reducing both platelet adhesion to the capillary wall and capillary plugging in sepsis.

  6. Low density lipoprotein receptor-related protein 1 mediated endocytosis of β1-integrin influences cell adhesion and cell migration.

    PubMed

    Rabiej, Verena K; Pflanzner, Thorsten; Wagner, Timo; Goetze, Kristina; Storck, Steffen E; Eble, Johannes A; Weggen, Sascha; Mueller-Klieser, Wolfgang; Pietrzik, Claus U

    2016-01-01

    The low density lipoprotein receptor-related protein 1 (LRP1) has been shown to interact with β1-integrin and regulate its surface expression. LRP1 knock-out cells exhibit altered cytoskeleton organization and decreased cell migration. Here we demonstrate coupled endocytosis of LRP1 and β1-integrin and the involvement of the intracellular NPxY2 motif of LRP1 in this process. Mouse embryonic fibroblasts harboring a knock in replacement of the NPxY2 motif of LRP1 by a multiple alanine cassette (AAxA) showed elevated surface expression of β1-integrin and decreased β1-integrin internalization rates. As a consequence, cell spreading was altered and adhesion rates were increased in our cell model. Cells formed more focal adhesion complexes, whereby in vitro cell migration rates were decreased. Similar results could be observed in a corresponding mouse model, the C57Bl6 LRP1 NPxYxxL knock in mice, therefore, the biochemistry of cellular adhesion was altered in primary cortical neurons. In vivo cell migration experiments demonstrated a disturbance of neuroblast cell migration along the rostral migratory stream. In summary, our results indicate that LRP1 interacts with β1-integrin mediating integrin internalization and thus correlates with downstream signaling of β1-integrin such as focal adhesion dynamics. Consequently, the disturbance of this interaction resulted in a dysfunction in in vivo and in vitro cell adhesion and cell migration.

  7. Suppression of complement regulatory protein C1 inhibitor in vascular endothelial activation by inhibiting vascular cell adhesion molecule-1 action

    SciTech Connect

    Zhang, Haimou; Qin, Gangjian; Liang, Gang; Li, Jinan; Chiu, Isaac; Barrington, Robert A.; Liu, Dongxu . E-mail: dxliu001@yahoo.com

    2007-07-13

    Increased expression of adhesion molecules by activated endothelium is a critical feature of vascular inflammation associated with the several diseases such as endotoxin shock and sepsis/septic shock. Our data demonstrated complement regulatory protein C1 inhibitor (C1INH) prevents endothelial cell injury. We hypothesized that C1INH has the ability of an anti-endothelial activation associated with suppression of expression of adhesion molecule(s). C1INH blocked leukocyte adhesion to endothelial cell monolayer in both static assay and flow conditions. In inflammatory condition, C1INH reduced vascular cell adhesion molecule (VCAM-1) expression associated with its cytoplasmic mRNA destabilization and nuclear transcription level. Studies exploring the underlying mechanism of C1INH-mediated suppression in VCAM-1 expression were related to reduction of NF-{kappa}B activation and nuclear translocation in an I{kappa}B{alpha}-dependent manner. The inhibitory effects were associated with reduction of inhibitor I{kappa}B kinase activity and stabilization of the NF-{kappa}B inhibitor I{kappa}B. These findings indicate a novel role for C1INH in inhibition of vascular endothelial activation. These observations could provide the basis for new therapeutic application of C1INH to target inflammatory processes in different pathologic situations.

  8. Omentin inhibits TNF-α-induced expression of adhesion molecules in endothelial cells via ERK/NF-κB pathway.

    PubMed

    Zhong, Xia; Li, Xiaonan; Liu, Fuli; Tan, Hui; Shang, Deya

    2012-08-24

    In the present study, we investigated whether omentin affected the expression of intracellular adhesion molecule-1 (ICAM-1) and vascular cell adhesion molecule-1 (VCAM-1) in tumor necrosis factor-α (TNF-α) induced human umbilical vein endothelial cells (HUVECs). Our data showed that omentin decreased TNF-α-induced expression of ICAM-1 and VCAM-1 in HUVECs. In addition, omentin inhibited TNF-α-induced adhesion of THP-1 cells to HUVECs. Further, we found that omentin inhibited TNF-α-activated signal pathway of nuclear factor-κB (NF-κB) by preventing NF-κB inhibitory protein (IκBα) degradation and NF-κB/DNA binding activity. Omentin pretreatment significantly inhibited TNF-α-induced ERK activity and ERK phosphorylation in HUVECs. Pretreatment with PD98059 suppressed TNF-α-induced NF-κB activity. Omentin, NF-kB inhibitor (BAY11-7082) and ERK inhibitor (PD98059) reduced the up-regulation of ICAM-1 and VCAM-1 induced by TNF-α. These results suggest that omentin may inhibit TNF-α-induced expression of adhesion molecules in endothelial cells via blocking ERK/NF-κB pathway.

  9. Maltose-Binding Protein (MBP), a Secretion-Enhancing Tag for Mammalian Protein Expression Systems.

    PubMed

    Reuten, Raphael; Nikodemus, Denise; Oliveira, Maria B; Patel, Trushar R; Brachvogel, Bent; Breloy, Isabelle; Stetefeld, Jörg; Koch, Manuel

    2016-01-01

    Recombinant proteins are commonly expressed in eukaryotic expression systems to ensure the formation of disulfide bridges and proper glycosylation. Although many proteins can be expressed easily, some proteins, sub-domains, and mutant protein versions can cause problems. Here, we investigated expression levels of recombinant extracellular, intracellular as well as transmembrane proteins tethered to different polypeptides in mammalian cell lines. Strikingly, fusion of proteins to the prokaryotic maltose-binding protein (MBP) generally enhanced protein production. MBP fusion proteins consistently exhibited the most robust increase in protein production in comparison to commonly used tags, e.g., the Fc, Glutathione S-transferase (GST), SlyD, and serum albumin (ser alb) tag. Moreover, proteins tethered to MBP revealed reduced numbers of dying cells upon transient transfection. In contrast to the Fc tag, MBP is a stable monomer and does not promote protein aggregation. Therefore, the MBP tag does not induce artificial dimerization of tethered proteins and provides a beneficial fusion tag for binding as well as cell adhesion studies. Using MBP we were able to secret a disease causing laminin β2 mutant protein (congenital nephrotic syndrome), which is normally retained in the endoplasmic reticulum. In summary, this study establishes MBP as a versatile expression tag for protein production in eukaryotic expression systems.

  10. Omentin inhibits TNF-{alpha}-induced expression of adhesion molecules in endothelial cells via ERK/NF-{kappa}B pathway

    SciTech Connect

    Zhong, Xia; Li, Xiaonan; Liu, Fuli; Tan, Hui; Shang, Deya

    2012-08-24

    Highlights: Black-Right-Pointing-Pointer Omentin inhibited TNF-{alpha}-induced adhesion of THP-1 cells to HUVECs. Black-Right-Pointing-Pointer Omentin reduces expression of ICAM-1 and VCAM-1 induced by TNF-{alpha} in HUVECs. Black-Right-Pointing-Pointer Omentin inhibits TNF-{alpha}-induced ERK and NF-{kappa}B activation in HUVECs. Black-Right-Pointing-Pointer Omentin supreeses TNF-{alpha}-induced expression of ICAM-1 and VCAM-1 via ERK/NF-{kappa}B pathway. -- Abstract: In the present study, we investigated whether omentin affected the expression of intracellular adhesion molecule-1 (ICAM-1) and vascular cell adhesion molecule-1 (VCAM-1) in tumor necrosis factor-{alpha} (TNF-{alpha}) induced human umbilical vein endothelial cells (HUVECs). Our data showed that omentin decreased TNF-{alpha}-induced expression of ICAM-1 and VCAM-1 in HUVECs. In addition, omentin inhibited TNF-{alpha}-induced adhesion of THP-1 cells to HUVECs. Further, we found that omentin inhibited TNF-{alpha}-activated signal pathway of nuclear factor-{kappa}B (NF-{kappa}B) by preventing NF-{kappa}B inhibitory protein (I{kappa}B{alpha}) degradation and NF-{kappa}B/DNA binding activity. Omentin pretreatment significantly inhibited TNF-{alpha}-induced ERK activity and ERK phosphorylation in HUVECs. Pretreatment with PD98059 suppressed TNF-{alpha}-induced NF-{kappa}B activity. Omentin, NF-kB inhibitor (BAY11-7082) and ERK inhibitor (PD98059) reduced the up-regulation of ICAM-1 and VCAM-1 induced by TNF-{alpha}. These results suggest that omentin may inhibit TNF-{alpha}-induced expression of adhesion molecules in endothelial cells via blocking ERK/NF-{kappa}B pathway.

  11. Protein Recovery from Secondary Paper Sludge and Its Potential Use as Wood Adhesive

    NASA Astrophysics Data System (ADS)

    Pervaiz, Muhammad

    Secondary sludge is an essential part of biosolids produced through the waste treatment plant of paper mills. Globally paper mills generate around 3.0 million ton of biosolids and in the absence of beneficial applications, the handling and disposal of this residual biomass poses a serious environmental and economic proposition. Secondary paper sludges were investigated in this work for recovery of proteins and their use as wood adhesive. After identifying extracellular polymeric substances as adhesion pre-cursors through analytical techniques, studies were carried out to optimize protein recovery from SS and its comprehensive characterization. A modified physicochemical protocol was developed to recover protein from secondary sludge in substantial quantities. The combined effect of French press and sonication techniques followed by alkali treatment resulted in significant improvement of 44% in the yield of solubilized protein compared to chemical methods. The characterization studies confirmed the presence of common amino acids in recovered sludge protein in significant quantities and heavy metal concentration was reduced after recovery process. The sodium dodecyl sulfate polyacrylamide gel electrophoresis analysis revealed the presence of both low and high molecular weight protein fractions in recovered sludge protein. After establishing the proof-of-concept in the use of recovered sludge protein as wood adhesive, the bonding mechanism of protein adhesives with cellulose substrate was further elucidated in a complementary protein-modification study involving soy protein isolate and its glycinin fractions. The results of this study validated the prevailing bonding theories by proving that surface wetting, protein structure, and type of wood play important role in determining final adhesive strength. Recovered sludge protein was also investigated for its compatibility to formulate hybrid adhesive blends with formaldehyde and bio-based polymers. Apart from chemical

  12. Embedded proteins and sacrificial bonds provide the strong adhesive properties of gastroliths

    NASA Astrophysics Data System (ADS)

    Thormann, Esben; MizunoPresent Address: Nihon L'Oreal, Research; Innovation Center, 3-2-1 Sakado, Takatsu, Kawasaki, Kanagawa, Japan., Hiroyasu; Jansson, Kjell; Hedin, Niklas; Fernández, M. Soledad; Arias, José Luis; Rutland, Mark W.; PaiPresent Address: CenterFunctional Nanomaterials, Brookhaven National Laboratory, 735 Brookhaven Avenue, Upton, New York 11973., Ranjith Krishna; Bergström, Lennart

    2012-06-01

    The adhesive properties of gastroliths from a freshwater crayfish (Cherax quadricarinatus) were quantified by colloidal probe atomic force microscopy (AFM) between heavily demineralized gastrolith microparticles and gastrolith substrates of different composition. Combined AFM and transmission electron microscopy studies demonstrated that the sequential detachment and large adhesion energies that characterise the adhesive behaviour of a native gastrolith substrate are dominated by sacrificial bonds between chitin fibres and between chitin fibres and CaCO3. The sacrificial bonds were shown to be strongly related to the gastrolith proteins and when the majority of these proteins were removed by ethylenediaminetetraacetic acid (EDTA), the sequential detachment disappeared and the adhesive energy was reduced by more than two orders of magnitude.The adhesive properties of gastroliths from a freshwater crayfish (Cherax quadricarinatus) were quantified by colloidal probe atomic force microscopy (AFM) between heavily demineralized gastrolith microparticles and gastrolith substrates of different composition. Combined AFM and transmission electron microscopy studies demonstrated that the sequential detachment and large adhesion energies that characterise the adhesive behaviour of a native gastrolith substrate are dominated by sacrificial bonds between chitin fibres and between chitin fibres and CaCO3. The sacrificial bonds were shown to be strongly related to the gastrolith proteins and when the majority of these proteins were removed by ethylenediaminetetraacetic acid (EDTA), the sequential detachment disappeared and the adhesive energy was reduced by more than two orders of magnitude. Electronic supplementary information (ESI) available. See DOI: 10.1039/c2nr30536d

  13. Experimental strategies for the identification and characterization of adhesive proteins in animals: a review

    PubMed Central

    Hennebert, Elise; Maldonado, Barbara; Ladurner, Peter; Flammang, Patrick; Santos, Romana

    2015-01-01

    Adhesive secretions occur in both aquatic and terrestrial animals, in which they perform diverse functions. Biological adhesives can therefore be remarkably complex and involve a large range of components with different functions and interactions. However, being mainly protein based, biological adhesives can be characterized by classical molecular methods. This review compiles experimental strategies that were successfully used to identify, characterize and obtain the full-length sequence of adhesive proteins from nine biological models: echinoderms, barnacles, tubeworms, mussels, sticklebacks, slugs, velvet worms, spiders and ticks. A brief description and practical examples are given for a variety of tools used to study adhesive molecules at different levels from genes to secreted proteins. In most studies, proteins, extracted from secreted materials or from adhesive organs, are analysed for the presence of post-translational modifications and submitted to peptide sequencing. The peptide sequences are then used directly for a BLAST search in genomic or transcriptomic databases, or to design degenerate primers to perform RT-PCR, both allowing the recovery of the sequence of the cDNA coding for the investigated protein. These sequences can then be used for functional validation and recombinant production. In recent years, the dual proteomic and transcriptomic approach has emerged as the best way leading to the identification of novel adhesive proteins and retrieval of their complete sequences. PMID:25657842

  14. PERP regulates enamel formation via effects on cell–cell adhesion and gene expression

    PubMed Central

    Jheon, Andrew H.; Mostowfi, Pasha; Snead, Malcolm L.; Ihrie, Rebecca A.; Sone, Eli; Pramparo, Tiziano; Attardi, Laura D.; Klein, Ophir D.

    2011-01-01

    Little is known about the role of cell–cell adhesion in the development of mineralized tissues. Here we report that PERP, a tetraspan membrane protein essential for epithelial integrity, regulates enamel formation. PERP is necessary for proper cell attachment and gene expression during tooth development, and its expression is controlled by P63, a master regulator of stratified epithelial development. During enamel formation, PERP is localized to the interface between the enamel-producing ameloblasts and the stratum intermedium (SI), a layer of cells subjacent to the ameloblasts. Perp-null mice display dramatic enamel defects, which are caused, in part, by the detachment of ameloblasts from the SI. Microarray analysis comparing gene expression in teeth of wild-type and Perp-null mice identified several differentially expressed genes during enamel formation. Analysis of these genes in ameloblast-derived LS8 cells upon knockdown of PERP confirmed the role for PERP in the regulation of gene expression. Together, our data show that PERP is necessary for the integrity of the ameloblast–SI interface and that a lack of Perp causes downregulation of genes that are required for proper enamel formation. PMID:21285247

  15. Modulation of cell adhesion complexes by surface protein patterns.

    PubMed

    Pesen, Devrim; Haviland, David B

    2009-03-01

    Cell adhesion is an important process in several biological phenomena. To investigate the formation and organization of focal adhesions, we developed a patterning approach based on electron beam lithography. Nanodots (radius <1230 nm) and nanorings (inner radius <320 nm) of fibronectin (FN) were patterned on a K-Casein background. Intracellular vinculin immunofluorescence mirrored the FN nanopatterns. Atomic force microscopy showed that FN nanodots and nanorings organize the immediate cytoskeleton into straight fibrils and diverging fibril bundles, respectively. Our results suggest that a minimum of approximately 40 FN molecules is required for a cell to form a focal adhesion.

  16. Transforming growth factor beta-induced (TGFBI) is an anti-adhesive protein regulating the invasive growth of melanoma cells.

    PubMed

    Nummela, Pirjo; Lammi, Johanna; Soikkeli, Johanna; Saksela, Olli; Laakkonen, Pirjo; Hölttä, Erkki

    2012-04-01

    Melanoma is a malignancy characterized by high invasive/metastatic potential, with no efficient therapy after metastasis. Understanding the molecular mechanisms underlying the invasive/metastatic tendency is therefore important. Our genome-wide gene expression analyses revealed that human melanoma cell lines WM793 and especially WM239 (vertical growth phase and metastatic cells, respectively) overexpress the extracellular matrix (ECM) protein transforming growth factor β induced (TGFBI). In adhesion assays, recombinant TGFBI was strongly anti-adhesive for both melanoma cells and skin fibroblasts. TGFBI further impaired the adhesion of melanoma cells to the adhesive ECM proteins fibronectin, collagen-I, and laminin, known to interact with it. Unexpectedly, WM239 cells migrated/invaded more effectively in three-dimensional collagen-I and Matrigel cultures after knockdown of TGFBI by shRNA expression. However, in the physiological subcutaneous microenvironment in nude mice, after TGFBI knockdown, these cells showed markedly impaired tumor growth and invasive capability; the initially formed small tumors later underwent myxoid degeneration and completely regressed. By contrast, the expanding control tumors showed intense TGFBI staining at the tumor edges, co-localizing with the fibrillar fibronectin/tenascin-C/periostin structures that characteristically surround melanoma cells at invasion fronts. Furthermore, TGFBI was found in similar fibrillar structures in clinical human melanoma metastases as well, co-localizing with fibronectin. These data imply an important role for TGFBI in the ECM deposition and invasive growth of melanoma cells, rendering TGFBI a potential target for therapeutic interventions.

  17. Monitoring in real-time focal adhesion protein dynamics in response to a discrete mechanical stimulus.

    PubMed

    von Bilderling, Catalina; Caldarola, Martín; Masip, Martín E; Bragas, Andrea V; Pietrasanta, Lía I

    2017-01-01

    The adhesion of cells to the extracellular matrix is a hierarchical, force-dependent, multistage process that evolves at several temporal scales. An understanding of this complex process requires a precise measurement of forces and its correlation with protein responses in living cells. We present a method to quantitatively assess live cell responses to a local and specific mechanical stimulus. Our approach combines atomic force microscopy with fluorescence imaging. Using this approach, we evaluated the recruitment of adhesion proteins such as vinculin, focal adhesion kinase, paxillin, and zyxin triggered by applying forces in the nN regime to live cells. We observed in real time the development of nascent adhesion sites, evident from the accumulation of early adhesion proteins at the position where the force was applied. We show that the method can be used to quantify the recruitment characteristic times for adhesion proteins in the formation of focal complexes. We also found a spatial remodeling of the mature focal adhesion protein zyxin as a function of the applied force. Our approach allows the study of a variety of complex biological processes involved in cellular mechanotransduction.

  18. Orphan G protein-coupled receptor GPRC5A modulates integrin β1-mediated epithelial cell adhesion.

    PubMed

    Bulanova, Daria R; Akimov, Yevhen A; Rokka, Anne; Laajala, Teemu D; Aittokallio, Tero; Kouvonen, Petri; Pellinen, Teijo; Kuznetsov, Sergey G

    2016-10-07

    G-Protein Coupled Receptor (GPCR), Class C, Group 5, Member A (GPRC5A) has been implicated in several malignancies. The underlying mechanisms, however, remain poorly understood. Using a panel of human cell lines, we demonstrate that CRISPR/Cas9-mediated knockout and RNAi-mediated depletion of GPRC5A impairs cell adhesion to integrin substrates: collagens I and IV, fibronectin, as well as to extracellular matrix proteins derived from the Engelbreth-Holm-Swarm (EHS) mouse sarcoma (Matrigel). Consistent with the phenotype, knock-out of GPRC5A correlated with a reduced integrin β1 (ITGB1) protein expression, impaired phosphorylation of the focal adhesion kinase (FAK), and lower activity of small GTPases RhoA and Rac1. Furthermore, we provide the first evidence for a direct interaction between GPRC5A and a receptor tyrosine kinase EphA2, an upstream regulator of FAK, although its contribution to the observed adhesion phenotype is unclear. Our findings reveal an unprecedented role for GPRC5A in regulation of the ITGB1-mediated cell adhesion and it's downstream signaling, thus indicating a potential novel role for GPRC5A in human epithelial cancers.

  19. Expression of estrogen receptor beta increases integrin alpha1 and integrin beta1 levels and enhances adhesion of breast cancer cells.

    PubMed

    Lindberg, Karolina; Ström, Anders; Lock, John G; Gustafsson, Jan-Ake; Haldosén, Lars-Arne; Helguero, Luisa A

    2010-01-01

    Estrogen effects on mammary gland development and differentiation are mediated by two receptors (ERalpha and ERbeta). Estrogen-bound ERalpha induces proliferation of mammary epithelial and cancer cells, while ERbeta is important for maintenance of the differentiated epithelium and inhibits proliferation in different cell systems. In addition, the normal breast contains higher ERbeta levels compared to the early stage breast cancers, suggesting that loss of ERbeta could be important in cancer development. Analysis of ERbeta-/- mice has consistently revealed reduced expression of cell adhesion proteins. As such, ERbeta is a candidate modulator of epithelial homeostasis and metastasis. Consequently, the aim of this study was to analyze estrogenic effects on adhesion of breast cancer cells expressing ERalpha and ERbeta. As ERbeta is widely found in breast cancer but not in cell lines, we used ERalpha positive T47-D and MCF-7 human breast cancer cells to generate cells with inducible ERbeta expression. Furthermore, the colon cancer cell lines SW480 and HT-29 were also used. Integrin alpha1 mRNA and protein levels increased following ERbeta expression. Integrin beta1-the unique partner for integrin alpha1-increased only at the protein level. ERbeta expression enhanced the formation of vinculin containing focal complexes and actin filaments, indicating a more adhesive potential. This was confirmed by adhesion assays where ERbeta increased adhesion to different extracellular matrix proteins, mostly laminin. In addition, ERbeta expression was associated to less cell migration. These results indicate that ERbeta affects integrin expression and clustering and consequently modulates adhesion and migration of breast cancer cells.

  20. Cleavage of Type I Collagen by Fibroblast Activation Protein-α Enhances Class A Scavenger Receptor Mediated Macrophage Adhesion.

    PubMed

    Mazur, Anna; Holthoff, Emily; Vadali, Shanthi; Kelly, Thomas; Post, Steven R

    2016-01-01

    Pathophysiological conditions such as fibrosis, inflammation, and tumor progression are associated with modification of the extracellular matrix (ECM). These modifications create ligands that differentially interact with cells to promote responses that drive pathological processes. Within the tumor stroma, fibroblasts are activated and increase the expression of type I collagen. In addition, activated fibroblasts specifically express fibroblast activation protein-α (FAP), a post-prolyl peptidase. Although FAP reportedly cleaves type I collagen and contributes to tumor progression, the specific pathophysiologic role of FAP is not clear. In this study, the possibility that FAP-mediated cleavage of type I collagen modulates macrophage interaction with collagen was examined using macrophage adhesion assays. Our results demonstrate that FAP selectively cleaves type I collagen resulting in increased macrophage adhesion. Increased macrophage adhesion to FAP-cleaved collagen was not affected by inhibiting integrin-mediated interactions, but was abolished in macrophages lacking the class A scavenger receptor (SR-A/CD204). Further, SR-A expressing macrophages localize with activated fibroblasts in breast tumors of MMTV-PyMT mice. Together, these results demonstrate that FAP-cleaved collagen is a substrate for SR-A-dependent macrophage adhesion, and suggest that by modifying the ECM, FAP plays a novel role in mediating communication between activated fibroblasts and macrophages.

  1. Adhesion-Linked Protein Tyrosine Phosphatases, Morphogenesis and Breast Cancer Progression

    DTIC Science & Technology

    2004-07-01

    Award Number: DAMD17-03-1-0496 TITLE: Adhesion-linked Protein Tyrosine Phosphatases, Morphogenesis and Breast Cancer Progression PRINCIPAL...Adhesion-linked Protein Tyrosine Phosphatases, DAMD17-03-1-0496 Morphogenesis and Breast Cancer Progression 6. AUTHOR(S) Valerie M. Weaver, Ph.D. 7...we identified the Band 4.1 PTPs MEG1 and D1 as two candidate PTP metastasis suppressors. Our studies show that during MEC differentiation PTP MEG1

  2. Major Membrane Protein TDE2508 Regulates Adhesive Potency in Treponema denticola

    PubMed Central

    Abiko, Yuki; Nagano, Keiji; Yoshida, Yasuo; Yoshimura, Fuminobu

    2014-01-01

    The cultivation and genetic manipulation of Treponema denticola, a Gram-negative oral spirochaeta associated with periodontal diseases, is still challenging. In this study, we formulated a simple medium based on a commercially available one, and established a transformation method with high efficiency. We then analyzed proteins in a membrane fraction in T. denticola and identified 16 major membrane-associated proteins, and characterized one of them, TDE2508, whose biological function was not yet known. Although this protein, which exhibited a complex conformation, was presumably localized in the outer membrane, we did not find conclusive evidence that it was exposed on the cell surface. Intriguingly, a TDE2508-deficient mutant exhibited significantly increased biofilm formation and adherent activity on human gingival epithelial cells. However, the protein deficiency did not alter autoaggregation, coaggregation with Porphyromonas gingivalis, hemagglutination, cell surface hydrophobicity, motility, or expression of Msp which was reported to be an adherent molecule in this bacteria. In conclusion, the major membrane protein TDE2508 regulates biofilm formation and the adhesive potency of T. denticola, although the underlying mechanism remains unclear. PMID:24586498

  3. Phosphoproteome reveals an atlas of protein signaling networks during osteoblast adhesion.

    PubMed

    Milani, Renato; Ferreira, Carmen V; Granjeiro, José M; Paredes-Gamero, Edgar J; Silva, Rodrigo A; Justo, Giselle Z; Nader, Helena B; Galembeck, Eduardo; Peppelenbosch, Maikel P; Aoyama, Hiroshi; Zambuzzi, Willian F

    2010-04-01

    Cell adhesion on surfaces is a fundamental process in the emerging biomaterials field and developmental events as well. However, the mechanisms regulating this biological process in osteoblasts are not fully understood. Reversible phosphorylation catalyzed by kinases is probably the most important regulatory mechanism in eukaryotes. Therefore, the goal of this study is to assess osteoblast adhesion through a molecular prism under a peptide array technology, revealing essential signaling proteins governing adhesion-related events. First, we showed that there are main morphological changes on osteoblast shape during adhesion up to 3 h. Second, besides classical proteins activated upon integrin activation, our results showed a novel network involving signaling proteins such as Rap1A, PKA, PKC, and GSK3beta during osteoblast adhesion on polystyrene. Third, these proteins were grouped in different signaling cascades including focal adhesion establishment, cytoskeleton rearrangement, and cell-cycle arrest. We have thus provided evidence that a global phosphorylation screening is able to yield a systems-oriented look at osteoblast adhesion, providing new insights for understanding of bone formation and improvement of cell-substratum interactions. Altogether, these statements are necessary means for further intervention and development of new approaches for the progress of tissue engineering.

  4. Are conformational changes, induced by osmotic pressure variations, the underlying mechanism of controlling the adhesive activity of mussel adhesive proteins?

    PubMed

    van der Leeden, Mieke C

    2005-11-22

    The mussel adhesive protein Mefp-1, under physiological conditions, presumably has a self-avoiding random walk conformation with helix-like or turned deca-peptide segments. Such a conformation may coil up under osmotic pressure induced by surrounding macromolecules. As a consequence, the orientation of the 3,4-dihydroxy-phenylalanine groups (dopa), essential for the adhesive strength as well as the cohesive strength in Mefp-1, will be altered. Changing the concentration of the protein itself or of different-type surrounding macromolecules may therefore be a tool to control the protein's adhesive activity. The effect of osmotic pressure on the conformation and dopa reactivity of Mefp-1 is studied by the addition of (poly)ethylene oxide (PEO) as a model macromolecule (Mw = 100 kD). From UV-spectroscopy measurements, it can be concluded that dopa reactivity in Mefp-1 changes with increasing PEO concentration. Fitting of the measured absorbance intensity data of the oxidation product dopaquinone versus time with a kinetic model points to the decreased accessibility of dopa groups in the Mefp-1 structure, a faster oxidation, and diminished cross linking under the influence of increasing PEO concentration up to 2.4 g/L, corresponding to an osmotic pressure of approximately 73 Pa. At higher PEO concentrations, the accessibility of the dopa groups for oxidation as well as cross-link formation decreases until about 20% of the dopa groups are oxidized at a PEO concentration of 3.8 g/L, corresponding to an osmotic pressure of approximately 113 Pa. FTIR measurements on the basis of amide I shifts qualitatively point to a transition to a more continuously turned structure of Mefp-1 in the presence of PEO. Therefore, it seems that conformational changes caused by variations of osmotic pressure determine the extent of steric hindrance of the dopa groups and hence the adhesive reactivity of Mefp-1.

  5. Structural organization and function of mouse photoreceptor ribbon synapses involve the immunoglobulin protein synaptic cell adhesion molecule 1.

    PubMed

    Ribic, Adema; Liu, Xinran; Crair, Michael C; Biederer, Thomas

    2014-03-01

    Adhesive interactions in the retina instruct the developmental specification of inner retinal layers. However, potential roles of adhesion in the development and function of photoreceptor synapses remain incompletely understood. This contrasts with our understanding of synapse development in the CNS, which can be guided by select adhesion molecules such as the Synaptic Cell Adhesion Molecule 1 (SynCAM 1/CADM1/nectin-like 2 protein). This immunoglobulin superfamily protein modulates the development and plasticity of classical excitatory synapses. We show here by immunoelectron microscopy and immunoblotting that SynCAM 1 is expressed on mouse rod photoreceptors and their terminals in the outer nuclear and plexiform layers in a developmentally regulated manner. Expression of SynCAM 1 on rods is low in early postnatal stages (P3-P7) but increases after eye opening (P14). In support of functional roles in the photoreceptors, electroretinogram recordings demonstrate impaired responses to light stimulation in SynCAM 1 knockout (KO) mice. In addition, the structural integrity of synapses in the OPL requires SynCAM 1. Quantitative ultrastructural analysis of SynCAM 1 KO retina measured fewer fully assembled, triadic rod ribbon synapses. Furthermore, rod synapse ribbons are shortened in KO mice, and protein levels of Ribeye, a major structural component of ribbons, are reduced in SynCAM 1 KO retina. Together, our results implicate SynCAM 1 in the synaptic organization of the rod visual pathway and provide evidence for novel roles of synaptic adhesion in the structural and functional integrity of ribbon synapses.

  6. Role of surface layer collagen binding protein from indigenous Lactobacillus plantarum 91 in adhesion and its anti-adhesion potential against gut pathogen.

    PubMed

    Yadav, Ashok Kumar; Tyagi, Ashish; Kaushik, Jai Kumar; Saklani, Asha Chandola; Grover, Sunita; Batish, Virender Kumar

    2013-12-14

    Human feacal isolates were ascertain as genus Lactobacillus using specific primer LbLMA1/R16-1 and further identified as Lactobacillus plantarum with species specific primers Lpl-3/Lpl-2. 25 L. plantarum strains were further assessed for hydrophobicity following the microbial adhesion to hydrocarbons (MATH) method and colonization potentials based on their adherence to immobilized human collagen type-1. Surface proteins were isolated from selected L. plantarum 91(Lp91) strain. The purified collagen binding protein (Cbp) protein was assessed for its anti-adhesion activity against enteric Escherichia coli 0157:H7 pathogen on immobilized collagen. Four L. plantarum strains displayed high degree of hydrophobicity and significant adhesion to collagen. A 72 kDa protein was purified which reduced 59.71% adhesion of E. coli 0157:H7 on immobilized collagen as compared to control well during adhesion assay. Cbp protein is the major influencing factor in inhibition of E. coli 0157:H7 adhesion with extracellular matrix (ECM) components. Hydrophobicity and adhesion potential are closely linked attributes precipitating in better colonization potential of the lactobacillus strains. Cbp is substantiated as a crucial surface protein contributing in adhesion of lactobacillus strains. The study can very well be the platform for commercialization of indigenous probiotic strain once their functional attributes are clinically explored.

  7. Thymus cell antigen 1 (Thy1, CD90) is expressed by lymphatic vessels and mediates cell adhesion to lymphatic endothelium.

    PubMed

    Jurisic, Giorgia; Iolyeva, Maria; Proulx, Steven T; Halin, Cornelia; Detmar, Michael

    2010-10-15

    The lymphatic vascular system plays an important role in inflammation and cancer progression, although the molecular mechanisms involved are poorly understood. As determined by comparative transcriptional profiling studies of ex vivo isolated mouse intestinal lymphatic endothelial cells versus blood vascular endothelial cells, thymus cell antigen 1 (Thy1, CD90) was expressed at much higher levels in lymphatic endothelial cells than in blood vascular endothelial cells. These findings were confirmed by quantitative PCR, and at the protein level by FACS and immunofluorescence analyses. Thy1 was also strongly expressed by tumor-associated lymphatic vessels, as evaluated in a B16 melanoma footpad model in mice. Blockade of Thy1 inhibited tumor cell adhesion to cultured mouse lymphatic endothelial cells. Importantly, treatment of human dermal microvascular endothelial cells with tumor necrosis factor or phorbol 12-myristate 13-acetate resulted in Thy1 upregulation in podoplanin-expressing lymphatic endothelial cells, but not in podoplanin-negative blood vascular endothelial cells. Moreover, adhesion of human polymorphonuclear and mononuclear leukocytes to human lymphatic endothelial cells was Thy1-dependent. Together, these results identify Thy1 as a novel lymphatic vessel expressed gene and suggest its potential role in the cell adhesion processes required for tumor progression and inflammation.

  8. Modeling Protein Expression and Protein Signaling Pathways

    PubMed Central

    Telesca, Donatello; Müller, Peter; Kornblau, Steven M.; Suchard, Marc A.; Ji, Yuan

    2015-01-01

    High-throughput functional proteomic technologies provide a way to quantify the expression of proteins of interest. Statistical inference centers on identifying the activation state of proteins and their patterns of molecular interaction formalized as dependence structure. Inference on dependence structure is particularly important when proteins are selected because they are part of a common molecular pathway. In that case, inference on dependence structure reveals properties of the underlying pathway. We propose a probability model that represents molecular interactions at the level of hidden binary latent variables that can be interpreted as indicators for active versus inactive states of the proteins. The proposed approach exploits available expert knowledge about the target pathway to define an informative prior on the hidden conditional dependence structure. An important feature of this prior is that it provides an instrument to explicitly anchor the model space to a set of interactions of interest, favoring a local search approach to model determination. We apply our model to reverse-phase protein array data from a study on acute myeloid leukemia. Our inference identifies relevant subpathways in relation to the unfolding of the biological process under study. PMID:26246646

  9. Hypothermia Increases Tissue Plasminogen Activator Expression and Decreases Post-Operative Intra-Abdominal Adhesion

    PubMed Central

    Lee, Chien-Chang; Wang, Hsuan-Mao; Chou, Tzung-Hsin; Wu, Meng-Che; Hsueh, Kuang-Lung; Chen, Shyr-Chyr

    2016-01-01

    Background Therapeutic hypothermia during operation decreases postoperative intra-abdominal adhesion formation. We sought to determine the most appropriate duration of hypothermia, and whether hypothermia affects the expression of tissue plasminogen activator (tPA). Methods 80 male BALB/c mice weighing 25–30 g are randomized into one of five groups: adhesion model with infusion of 15°C saline for 15 minutes (A); 30 minutes (B); 45 minute (C); adhesion model without infusion of cold saline (D); and sham operation without infusion of cold saline (E). Adhesion scores and tPA levels in the peritoneum fluid levels were analyzed on postoperative days 1, 7, and 14. Results On day 14, the cold saline infusion groups (A, B, and C) had lower adhesion scores than the without infusion of cold saline group (D). However, only group B (cold saline infusion for 30 minutes) had a significantly lower adhesion scores than group D. Also, group B was found to have 3.4 fold, 2.3 fold, and 2.2 fold higher levels of tPA than group D on days 1, 7, and 14 respectively. Conclusions Our results suggest that cold saline infusion for 30 minutes was the optimum duration to decrease postoperative intra-abdominal adhesion formation. The decrease in the adhesion formations could be partly due to an increase in the level of tPA. PMID:27583464

  10. Adhesive surface proteins of Erysipelothrix rhusiopathiae bind to polystyrene, fibronectin, and type I and IV collagens.

    PubMed

    Shimoji, Yoshihiro; Ogawa, Yohsuke; Osaki, Makoto; Kabeya, Hidenori; Maruyama, Soichi; Mikami, Takeshi; Sekizaki, Tsutomu

    2003-05-01

    Erysipelothrix rhusiopathiae is a gram-positive bacterium that causes erysipelas in animals and erysipeloid in humans. We found two adhesive surface proteins of E. rhusiopathiae and determined the nucleotide sequences of the genes, which were colocalized and designated rspA and rspB. The two genes were present in all of the serovars of E. rhusiopathiae strains examined. The deduced RspA and RspB proteins contain the C-terminal anchoring motif, LPXTG, which is preceded by repeats of consensus amino acid sequences. The consensus sequences are composed of 78 to 92 amino acids and repeat 16 and 3 times in RspA and RspB, respectively. Adhesive surface proteins of other gram-positive bacteria, including Listeria monocytogenes adhesin-like protein, Streptococcus pyogenes protein F2 and F2-like protein, Streptococcus dysgalactiae FnBB, and Staphylococcus aureus Cna, share the same consensus repeats. Furthermore, the N-terminal regions of RspA and RspB showed characteristics of the collagen-binding domain that was described for Cna. RspA and RspB were expressed in Escherichia coli as histidine-tagged fusion proteins and purified. The recombinant proteins showed a high degree of capacity to bind to polystyrene and inhibited the binding of E. rhusiopathiae onto the abiotic surface in a dose dependent manner. In a solid-phase binding assay, both of the recombinant proteins bound to fibronectin, type I and IV collagens, indicating broad spectrum of their binding ability. It was suggested that both RspA and RspB were exposed on the cell surface of E. rhusiopathiae, as were the bacterial cells agglutinated by the anti-RspA immunoglobulin G (IgG) and anti-RspB IgG. RspA and RspB were present both in surface-antigen extracts and the culture supernatants of E. rhusiopathiae Fujisawa-SmR (serovar 1a) and SE-9 (serovar 2). The recombinant RspA, but not RspB, elicited protection in mice against experimental challenge. These results suggest that RspA and RspB participate in initiation

  11. Enhanced Adhesion of Campylobacter jejuni to Abiotic Surfaces Is Mediated by Membrane Proteins in Oxygen-Enriched Conditions

    PubMed Central

    Sulaeman, Sheiam; Hernould, Mathieu; Schaumann, Annick; Coquet, Laurent; Bolla, Jean-Michel; Dé, Emmanuelle; Tresse, Odile

    2012-01-01

    Campylobacter jejuni is responsible for the major foodborne bacterial enteritis in humans. In contradiction with its fastidious growth requirements, this microaerobic pathogen can survive in aerobic food environments, suggesting that it must employ a variety of protection mechanisms to resist oxidative stress. For the first time, C. jejuni 81–176 inner and outer membrane subproteomes were analyzed separately using two-dimensional protein electrophoresis (2-DE) of oxygen-acclimated cells and microaerobically grown cells. LC-MS/MS analyses successfully identified 42 and 25 spots which exhibited a significantly altered abundance in the IMP-enriched fraction and in the OMP-enriched fraction, respectively, in response to oxidative conditions. These spots corresponded to 38 membrane proteins that could be grouped into different functional classes: (i) transporters, (ii) chaperones, (iii) fatty acid metabolism, (iv) adhesion/virulence and (v) other metabolisms. Some of these proteins were up-regulated at the transcriptional level in oxygen-acclimated cells as confirmed by qRT-PCR. Downstream analyses revealed that adhesion of C. jejuni to inert surfaces and swarming motility were enhanced in oxygen-acclimated cells or paraquat-stressed cells, which could be explained by the higher abundance of membrane proteins involved in adhesion and biofilm formation. The virulence factor CadF, over-expressed in the outer membrane of oxygen-acclimated cells, contributes to the complex process of C. jejuni adhesion to inert surfaces as revealed by a reduction in the capability of C. jejuni 81–176 ΔCadF cells compared to the isogenic strain. Taken together, these data demonstrate that oxygen-enriched conditions promote the over-expression of membrane proteins involved in both the biofilm initiation and virulence of C. jejuni. PMID:23029510

  12. A mucus adhesion promoting protein, MapA, mediates the adhesion of Lactobacillus reuteri to Caco-2 human intestinal epithelial cells.

    PubMed

    Miyoshi, Yukihiro; Okada, Sanae; Uchimura, Tai; Satoh, Eiichi

    2006-07-01

    Lactobacillus reuteri is one of the dominant lactobacilli found in the gastrointestinal tract of various animals. A surface protein of L. reuteri 104R, mucus adhesion promoting protein (MapA), is considered to be an adhesion factor of this strain. We investigated the relation between MapA and adhesion of L. reuteri to human intestinal (Caco-2) cells. Quantitative analysis of the adhesion of L. reuteri strains to Caco-2 cells showed that various L. reuteri strains bind not only to mucus but also to intestinal epithelial cells. In addition, purified MapA bound to Caco-2 cells, and this binding inhibited the adhesion of L. reuteri in a concentration-dependent manner. Based on these observations, the adhesion of L. reuteri appears due to the binding of MapA to receptor-like molecules on Caco-2 cells. Further, far-western analysis indicated the existence of multiple receptor-like molecules in Caco-2 cells.

  13. Renal cell carcinoma alters endothelial receptor expression responsible for leukocyte adhesion.

    PubMed

    Juengel, Eva; Krueger, Geraldine; Rutz, Jochen; Nelson, Karen; Werner, Isabella; Relja, Borna; Seliger, Barbara; Fisslthaler, Beate; Fleming, Ingrid; Tsaur, Igor; Haferkamp, Axel; Blaheta, Roman A

    2016-04-12

    Renal cell carcinoma (RCC) escapes immune recognition. To elaborate the escape strategy the influence of RCC cells on endothelial receptor expression and endothelial leukocyte adhesion was evaluated. Human umbilical vein endothelial cells (HUVEC) were co-cultured with the RCC cell line, Caki-1, with and without tumor necrosis factor (TNF)-alpha. Intercellular cell adhesion molecule-1 (ICAM-1), vascular cell adhesion molecule-1 (VCAM-1), endothelial (E)-selectin, standard and variants (V) of CD44 were then analysed in HUVEC, using flow cytometry and Western blot analysis. To determine which components are responsible for HUVEC-Caki-1 interaction causing receptor alteration, Caki-1 membrane fragments versus cell culture supernatant were applied to HUVECS. Adhesion of peripheral blood lymphocytes (PBL) and polymorphonuclear neutrophils (PMN) to endothelium was evaluated by co-culture adhesion assays. Relevance of endothelial receptor expression for adhesion to endothelium was determined by receptor blockage. Co-culture of RCC and HUVECs resulted in a significant increase in endothelial ICAM-1, VCAM-1, E-selectin, CD44 V3 and V7 expression. Previous stimulation of HUVECs with TNF-alpha and co-cultivation with Caki-1 resulted in further elevation of endothelial CD44 V3 and V7 expression, whereas ICAM-1, VCAM-1 and E-selectin expression were significantly diminished. Since Caki-1 membrane fragments also caused these alterations, but cell culture supernatant did not, cell-cell contact may be responsible for this process. Blocking ICAM-1, VCAM-1, E-selectin or CD44 with respective antibodies led to a significant decrease in PBL and PMN adhesion to endothelium. Thus, exposing HUVEC to Caki-1 results in significant alteration of endothelial receptor expression and subsequent endothelial attachment of PBL and PMN.

  14. Strong underwater adhesives made by self-assembling multi-protein nanofibres.

    PubMed

    Zhong, Chao; Gurry, Thomas; Cheng, Allen A; Downey, Jordan; Deng, Zhengtao; Stultz, Collin M; Lu, Timothy K

    2014-10-01

    Many natural underwater adhesives harness hierarchically assembled amyloid nanostructures to achieve strong and robust interfacial adhesion under dynamic and turbulent environments. Despite recent advances, our understanding of the molecular design, self-assembly and structure-function relationships of these natural amyloid fibres remains limited. Thus, designing biomimetic amyloid-based adhesives remains challenging. Here, we report strong and multi-functional underwater adhesives obtained from fusing mussel foot proteins (Mfps) of Mytilus galloprovincialis with CsgA proteins, the major subunit of Escherichia coli amyloid curli fibres. These hybrid molecular materials hierarchically self-assemble into higher-order structures, in which, according to molecular dynamics simulations, disordered adhesive Mfp domains are exposed on the exterior of amyloid cores formed by CsgA. Our fibres have an underwater adhesion energy approaching 20.9 mJ m(-2), which is 1.5 times greater than the maximum of bio-inspired and bio-derived protein-based underwater adhesives reported thus far. Moreover, they outperform Mfps or curli fibres taken on their own and exhibit better tolerance to auto-oxidation than Mfps at pH ≥ 7.0.

  15. Strong underwater adhesives made by self-assembling multi-protein nanofibres

    NASA Astrophysics Data System (ADS)

    Zhong, Chao; Gurry, Thomas; Cheng, Allen A.; Downey, Jordan; Deng, Zhengtao; Stultz, Collin M.; Lu, Timothy K.

    2014-10-01

    Many natural underwater adhesives harness hierarchically assembled amyloid nanostructures to achieve strong and robust interfacial adhesion under dynamic and turbulent environments. Despite recent advances, our understanding of the molecular design, self-assembly and structure-function relationships of these natural amyloid fibres remains limited. Thus, designing biomimetic amyloid-based adhesives remains challenging. Here, we report strong and multi-functional underwater adhesives obtained from fusing mussel foot proteins (Mfps) of Mytilus galloprovincialis with CsgA proteins, the major subunit of Escherichia coli amyloid curli fibres. These hybrid molecular materials hierarchically self-assemble into higher-order structures, in which, according to molecular dynamics simulations, disordered adhesive Mfp domains are exposed on the exterior of amyloid cores formed by CsgA. Our fibres have an underwater adhesion energy approaching 20.9 mJ m-2, which is 1.5 times greater than the maximum of bio-inspired and bio-derived protein-based underwater adhesives reported thus far. Moreover, they outperform Mfps or curli fibres taken on their own and exhibit better tolerance to auto-oxidation than Mfps at pH ≥ 7.0.

  16. Localization of vascular adhesion protein-1 (VAP-1) in the human eye.

    PubMed

    Almulki, Lama; Noda, Kousuke; Nakao, Shintaro; Hisatomi, Toshio; Thomas, Kennard L; Hafezi-Moghadam, Ali

    2010-01-01

    Recently we showed a critical role for Vascular Adhesion Protein-1 (VAP-1) in rodents during acute ocular inflammation, angiogenesis, and diabetic retinal leukostasis. However, the expression of VAP-1 in the human eye is unknown. VAP-1 localization was therefore investigated by immunohistochemistry. Five micrometer thick sections were generated from human ocular tissues embedded in paraffin. Sections were incubated overnight with primary mAbs against VAP-1 (5 microg/ml), smooth muscle actin (1 microg/ml), CD31 or isotype-matched IgG at 4 degrees C. Subsequently, a secondary mAb was used for 30 min at room temperature, followed by Dako Envision + HRP (AEC) System for signal detection. The stained sections were examined using light microscopy and the signal intensity was quantified by two evaluators and graded into 4 discrete categories. In all examined ocular tissues, VAP-1 staining was confined to the vasculature. VAP-1 labeling showed the highest intensity in both arteries and veins of neuronal tissues: retina and optic nerve, and the lowest intensity in the iris vasculature (p < 0.05). Scleral and choroidal vessels showed moderate staining for VAP-1. VAP-1 intensity was significantly higher in the arteries compared to veins (p < 0.05). Furthermore, VAP-1 staining in arteries colocalized with both CD31 and smooth muscle actin (sm-actin) staining, suggesting expression of VAP-1 in endothelial cells, smooth muscle cells or potentially pericytes. In conclusion, immunohistochemistry reveals constitutive expression of VAP-1 in human ocular tissues. VAP-1 expression is nearly exclusive to the vasculature with arteries showing significantly higher expression than veins. Furthermore, VAP-1 expression in the ocular vasculature is heterogeneous, with the vessels of the optic nerve and the retina showing highest expressions. These results characterize VAP-1 expression in human ocular tissues.

  17. Localization of Vascular Adhesion Protein-1 (VAP-1) in the Human Eye

    PubMed Central

    Almulki, Lama; Noda, Kousuke; Nakao, Shintaro; Hisatomi, Toshio; Thomas, Kennard L.; Hafezi-Moghadam, Ali

    2009-01-01

    Recently we showed a critical role for Vascular Adhesion Protein-1 (VAP-1) in rodents during acute ocular inflammation, angiogenesis, and diabetic retinal leukostasis. However, the expression of VAP-1 in the human eye is unknown. VAP-1 localization was investigated by immunohistochemistry. Five μm thick sections were generated from human ocular tissues embedded in paraffin. Sections were incubated overnight with primary mAbs against VAP-1 (5μg/ml), smooth muscle actin (1μg/ml), CD31 or isotype-matched IgG at 4°C. Subsequently, a secondary mAb was used for 30min at room temperature, followed by Dako Envision + HRP (AEC) System for signal detection. The stained sections were examined using light microscopy and the signal intensity was quantified by two masked evaluators and graded into 4 discrete categories. In all examined ocular tissues, VAP-1 staining was confined to the vasculature. VAP-1 labeling showed the highest intensity in both arteries and veins of neuronal tissues; retina, and optic nerve, and the lowest intensity in the iris vasculature (p<0.05). Scleral and choroidal vessels showed moderate staining for VAP-1. VAP-1 intensity was significantly higher in the arteries compared to veins (p<0.05). Furthermore, VAP-1 staining in arteries co-localized with both CD31 and smooth muscle actin (sm-actin) staining, suggesting expression of VAP-1 in endothelial cells, smooth muscle cells or potentially pericytes. In conclusion, Immunohistochemistry reveals constitutive expression of VAP-1 in human ocular tissues. VAP-1 expression is exclusive to the vasculature with arteries showing significantly higher expression than veins. Furthermore, VAP-1 expression in the ocular vasculature is heterogeneous, with the vessels of the optic nerve and the retina showing highest expressions. These results characterize VAP-1 expression in human ocular tissues. PMID:19761765

  18. Preliminary studies of the effects of vascular adhesion protein-1 inhibitors on experimental corneal neovascularization.

    PubMed

    Enzsöly, Anna; Dunkel, Petra; Récsán, Zsuzsa; Gyorffy, Hajnalka; Tóth, Jeanette; Marics, Gábor; Bori, Zoltán; Tóth, Miklós; Zelkó, Romána; Di Paolo, Maria Luisa; Mátyus, Péter; Németh, János

    2011-07-01

    Vascular adhesion protein-1 (VAP-1) controls the adhesion of lymphocytes to endothelial cells and is upregulated at sites of inflammation. Moreover, it expresses amine oxidase activity, due to the sequence identity with semicarbazide-sensitive amine oxidase. Recent studies indicate a significant role for VAP-1 in neovascularization, besides its contribution to inflammation. Pathological blood vessel development in severe ocular diseases (such as diabetes, age-related macula degeneration, trauma and infections) might lead to decreased visual acuity and finally to blindness, yet there is no clear consensus as to its appropriate treatment. In the present case study, the effects of two VAP-1 inhibitors on experimentally induced corneal neovascularization in rabbits were compared with the effects of a known inhibitor of angiogenesis, bevacizumab, an anti-vascular endothelial growth factor antibody. In accordance with recent literature data, the results of the preliminary study reported here indicate that the administration of VAP-1 inhibitors is a potentially valuable therapeutic option in the treatment of corneal neovascularization.

  19. Babesia bovis expresses a neutralization-sensitive antigen that contains a microneme adhesive repeat (MAR) domain

    Technology Transfer Automated Retrieval System (TEKTRAN)

    A gene coding for a protein with sequence similarity to the Toxoplasma gondii micronemal 1 (MIC1) protein that contains a copy of a domain described as a sialic acid-binding micronemal adhesive repeat was identified in the Babesia bovis genome. The single copy gene, located in chromosome 3, contains...

  20. Expression of focal adhesion kinase in endometrial stromal cells of women with endometriosis was adjusted by ovarian steroid hormones.

    PubMed

    Mu, Lin; Ma, Yan-Yan

    2015-01-01

    The aim of our study is to investigate the effects of ovarian steroid hormones on focal adhesion kinase (FAK) expression in ESCs and whether there is alteration in women with endometriosis. FAK expression was assessed by western blotting analysis. Elevated expression of FAK was seen in the cultured ESCs treated with estrogen (P < 0.05). Expression of FAK protein was not changed in ESCs after treated by progesterone or treated by estrogen and progesterone. The level of up-regulation by estrogen in endometriosis is significantly higher than that from women without endometriosis (P < 0.05). FAK expression in endometrial stromal cells from endometriosis was more sensitive to estrogen, which might contribute to the pathogenesis and progress of endometriosis.

  1. AB223. Expression of tight junction proteins in rat vagina

    PubMed Central

    Oh, Kyung Jin; Lee, Hyun-Suk; Chung, Ho Suck; Ahn, Kyu Youn; Park, Kwangsung

    2014-01-01

    Aim Tight junction plays a role in apical cell-to-cell adhesion and epithelial polarity. In this study, we investigated the expression of tight junction proteins, such as Claudin-1, zonula occludens (ZO)-1, junction adhesion molecule (JAM)-A, and occludin in rat vagina. Methods Female Sprague-dawley rats (230-240 g, n=20) were divided into two groups: control (n=10) and bilateral ovariectomy (n=10). The expression and cellular localization of claudin-1, ZO-1, JAM-A, and occludin were determined in each group by immunohistochemistry and Western blot. Results Immunolabeling of ZO-1 was mainly expressed in the capillaries and venules of the vagina. Claudin-1, JAM-A, and occludin were expressed in the epithelium of the vagina. The immunoreactivity and protein expression of claudin-1 was significantly decreased in the ovariectomy group compared with the control group. Conclusions Our results suggest that tight junction proteins may have an important role in the vagina. Further studies are needed to clarify the role of each tight junction protein on vaginal lubrication.

  2. Comparative genome-based identification of a cell wall-anchored protein from Lactobacillus plantarum increases adhesion of Lactococcus lactis to human epithelial cells.

    PubMed

    Zhang, Bo; Zuo, Fanglei; Yu, Rui; Zeng, Zhu; Ma, Huiqin; Chen, Shangwu

    2015-09-15

    Adhesion to host cells is considered important for Lactobacillus plantarum as well as other lactic acid bacteria (LAB) to persist in human gut and thus exert probiotic effects. Here, we sequenced the genome of Lt. plantarum strain NL42 originating from a traditional Chinese dairy product, performed comparative genomic analysis and characterized a novel adhesion factor. The genome of NL42 was highly divergent from its closest neighbors, especially in six large genomic regions. NL42 harbors a total of 42 genes encoding adhesion-associated proteins; among them, cwaA encodes a protein containing multiple domains, including five cell wall surface anchor repeat domains and an LPxTG-like cell wall anchor motif. Expression of cwaA in Lactococcus lactis significantly increased its autoaggregation and hydrophobicity, and conferred the new ability to adhere to human colonic epithelial HT-29 cells by targeting cellular surface proteins, and not carbohydrate moieties, for CwaA adhesion. In addition, the recombinant Lc. lactis inhibited adhesion of Staphylococcus aureus and Escherichia coli to HT-29 cells, mainly by exclusion. We conclude that CwaA is a novel adhesion factor in Lt. plantarum and a potential candidate for improving the adhesion ability of probiotics or other bacteria of interest.

  3. GPR116, an adhesion G-protein-coupled receptor, promotes breast cancer metastasis via the Gαq-p63RhoGEF-Rho GTPase pathway.

    PubMed

    Tang, Xiaolong; Jin, Rongrong; Qu, Guojun; Wang, Xiu; Li, Zhenxi; Yuan, Zengjin; Zhao, Chen; Siwko, Stefan; Shi, Tieliu; Wang, Ping; Xiao, Jianru; Liu, Mingyao; Luo, Jian

    2013-10-15

    Adhesion G-protein-coupled receptors (GPCR), which contain adhesion domains in their extracellular region, have been found to play important roles in cell adhesion, motility, embryonic development, and immune response. Because most adhesion molecules with adhesion domains have vital roles in cancer metastasis, we speculated that adhesion GPCRs are potentially involved in cancer metastasis. In this study, we identified GPR116 as a novel regulator of breast cancer metastasis through expression and functional screening of the adhesion GPCR family. We found that knockdown of GPR116 in highly metastatic (MDA-MB-231) breast cancer cells suppressed cell migration and invasion. Conversely, ectopic GPR116 expression in poorly metastatic (MCF-7 and Hs578T) cells promoted cell invasion. We further showed that knockdown of GPR116 inhibited breast cancer cell metastasis in two mammary tumor metastasis mouse models. Moreover, GPR116 modulated the formation of lamellipodia and actin stress fibers in cells in a RhoA- and Rac1-dependent manner. At a molecular level, GPR116 regulated cell motility and morphology through the Gαq-p63RhoGEF-RhoA/Rac1 pathway. The biologic significance of GPR116 in breast cancer is substantiated in human patient samples, where GPR116 expression is significantly correlated with breast tumor progression, recurrence, and poor prognosis. These findings show that GPR116 is crucial for the metastasis of breast cancer and support GPR116 as a potential prognostic marker and drug target against metastatic human breast cancer.

  4. Adhesion protein VSIG1 is required for the proper differentiation of glandular gastric epithelia.

    PubMed

    Oidovsambuu, Odgerel; Nyamsuren, Gunsmaa; Liu, Shuai; Göring, Wolfgang; Engel, Wolfgang; Adham, Ibrahim M

    2011-01-01

    VSIG1, a cell adhesion protein of the immunoglobulin superfamily, is preferentially expressed in stomach, testis, and certain gastric, esophageal and ovarian cancers. Here, we describe the expression patterns of three alternatively spliced isoforms of mouse Vsig1 during pre- and postnatal development of stomach and potential function of Vsig1 in differentiation of gastric epithelia. We show that isoforms Vsig1A and Vsig1B, which differ in the 3'untranslated region, are expressed in the early stages of stomach development. Immunohistochemical analysis revealed that VSIG1 is restricted to the adherens junction of the glandular epithelium. The shorter transcript Vsig1C is restricted to the testis, encodes an N-terminal truncated protein and is presumably regulated by an internal promoter, which is located upstream of exon 1b. To determine whether the 5' flanking region of exon 1a specifically targets the expression of Vsig1 to stomach epithelia, we generated and analyzed transgenic mice. The 4.8-kb fragment located upstream of exon 1a was sufficient to direct the expression of the reporter gene to the glandular epithelia of transgenic stomach. To determine the role of VSIG1 during the development of stomach epithelia, an X-linked Vsig1 was inactivated in embryonic stem cells (ESCs). Although Vsig1(-/Y) ESCs were only able to generate low coat color chimeric mice, no male chimeras transmitted the targeted allele to their progeny suggesting that the high contribution of Vsig1(-/Y) cells leads to the lethality of chimeric embryos. Analysis of chimeric stomachs revealed the differentiation of VSIG1-null cells into squamous epithelia inside the glandular region. These results suggest that VSIG1 is required for the establishment of glandular versus squamous epithelia in the stomach.

  5. Attenuation of leukocyte adhesion by recombinant TNF-binding protein after hemorrhagic shock in the rat.

    PubMed

    Maier, Marcus; Ströbele, Hubert; Voges, Jaqueline; Bauer, Clemens; Marzi, Ingo

    2003-05-01

    Ischemia/reperfusion injury involves a large number of humoral and cellular mediators that activate leukocytes that subsequently migrate to local tissues. Tumor necrosis factor (TNF)-alpha may be one of the most important mediators of this post-shock inflammatory response. In this study, we investigated the influence of a recombinant Type I (55 kDa) TNF-binding protein (TNF-BP) on leukocyte-endothelial interactions in the liver after hemorrhagic shock. Hemorrhagic shock was induced in female Sprague-Dawley rats (40 mmHg for 90 min) and a standardized resuscitation regimen was applied. At the time of resuscitation, animals were treated intravenously with either TNF-BP 4 mg/kg or placebo. The liver microcirculation was investigated using intravital fluorescence microscopy and immunohistochemistry at 5 h and 48 h after reperfusion. At 5 h, treatment with TNF-BP significantly reduced temporary leukocyte adhesion in the liver sinusoids as well as mean adhesion time of leukocytes in the hepatic central vein. In contrast, after 48 h, permanent leukocyte adhesion in the central hepatic vein was significantly reduced in the group receiving TNF-BP, whereas temporary leukocyte adhesion and mean adhesion time did not differ between the two groups. Both types of leukocyte adhesion, rolling adhesion after 5 h and firm adhesion after 48 h, were reduced in the group treated with TNF-BP, thereby suggesting a long-lasting anti-inflammatory effect.

  6. Diatom Adhesive Mucilage Contains Distinct Supramolecular Assemblies of a Single Modular Protein

    PubMed Central

    Dugdale, T. M.; Dagastine, R.; Chiovitti, A.; Wetherbee, R.

    2006-01-01

    A previous study used atomic force microscopy saw-tooth retraction curves to characterize the adhesive mucilage pads of the diatom Toxarium undulatum. The major mucilage component consisted of adhesive nanofibers (ANFs) made up of modular proteins arranged into cohesive units, each containing a set number of modular proteins aligned in parallel. This study shows that T. undulatum adhesive mucilage is a biocomposite containing four additional adhesive components, including single modular proteins that are likely to be the structural units from which the ANFs are assembled. Two further distinct supramolecular assemblies were observed to coexist with ANFs (ANFs II and III), along with a continuum of single modular proteins through oligomers made up of varying numbers of modular proteins arranged in parallel. All components of the adhesive biocomposite produce a characteristic force spectrum with the same interpeak distance (35.3 ± 0.3 (mean ± SE) nm), suggesting they are derived from discrete supramolecular assemblies of the same modular protein, but they are distinguishable from one another based on the rupture force, persistence length, and interpeak force measured from their saw-tooth curves. PMID:16443662

  7. A standardized bamboo leaf extract inhibits monocyte adhesion to endothelial cells by modulating vascular cell adhesion protein-1

    PubMed Central

    Choi, Sunga; Park, Myoung Soo; Lee, Yu Ran; Lee, Young Chul; Kim, Tae Woo; Do, Seon-Gil; Kim, Dong Seon

    2013-01-01

    Bamboo leaves (Phyllostachys pubescens Mazel ex J. Houz (Poacea)) have a long history of food and medical applications in Asia, including Japan and Korea. They have been used as a traditional medicine for centuries. We investigated the mechanism of anti-inflammatory activity of a bamboo leaf extract (BLE) on tumor necrosis factor-alpha (TNF-α)-induced monocyte adhesion in human umbilical vein endothelial cells (HUVECs). Exposure of HUVECs to BLE did not inhibit cell viability or cause morphological changes at concentrations ranging from 1 µg/ml to 1 mg/ml. Treatment with 0.1 mg/ml BLE caused 63% inhibition of monocyte adhesion in TNF-α-activated HUVECs, which was associated with 38.4% suppression of vascular cell adhesion molecule-1 expression. Furthermore, TNF-α-induced reactive oxygen species generation was decreased to 47.9% in BLE treated TNF-α-activated HUVECs. BLE (0.05 mg/ml) also caused about 50% inhibition of interleukin-6 secretion from lipopolysaccharide-stimulated monocyte. The results indicate that BLE may be clinically useful as an anti-inflammatory or anti-oxidant for human cardiovascular disease including atherosclerosis. PMID:23422838

  8. Expression of adhesion molecules, chemokines and matrix metallo- proteinases (MMPs) in viable and degenerating stage of Taenia solium metacestode in swine neurocysticercosis.

    PubMed

    Singh, Satyendra K; Singh, Aloukick K; Prasad, Kashi N; Singh, Amrita; Singh, Avinash; Rai, Ravi P; Tripathi, Mukesh; Gupta, Rakesh K; Husain, Nuzhat

    2015-11-30

    Neurocysticercosis (NCC) is a parasitic infection of central nervous system (CNS). Expression of adhesion molecules, chemokines and matrix metalloproteinases (MMPs) were investigated on brain tissues surrounding viable (n=15) and degenerating cysticerci (n=15) of Taenia solium in swine by real-time RT-PCR and ELISA. Gelatin gel zymography was performed for MMPs activity. ICAM-1 (intercellular adhesion molecule-1), E-selectin, MIP-1α (macrophage inflammatory protein-1α), Eotaxin-1 and RANTES (regulated on activation, normal T cell expressed and secreted) were associated with degenerating cysticerci (cysts). However, VCAM-1 (vascular cell adhesion molecule-1), MCP-1 (monocyte chemotactic protein-1), MMP-2 and MMP-9 were associated with both viable and degenerating cysts. In conclusion, viable and degenerating cysticerci have different immune molecule profiles and role of these molecules in disease pathogenesis needs to be investigated.

  9. Thrombospondin-1 up-regulates expression of cell adhesion molecules and promotes monocyte binding to endothelium

    PubMed Central

    Narizhneva, Natalya V.; Razorenova, Olga V.; Podrez, Eugene A.; Chen, Juhua; Chandrasekharan, Unni M.; DiCorleto, Paul E.; Plow, Edward F.; Topol, Eric J.; Byzova, Tatiana V.

    2006-01-01

    Expression of cell adhesion molecules (CAM) responsible for leukocyte-endothelium interactions plays a crucial role in inflammation and atherogenesis. Up-regulation of vascular CAM-1 (VCAM-1), intracellular CAM-1 (ICAM-1), and E-selectin expression promotes monocyte recruitment to sites of injury and is considered to be a critical step in atherosclerotic plaque development. Factors that trigger this initial response are not well understood. As platelet activation not only promotes thrombosis but also early stages of atherogenesis, we considered the role of thrombospondin-1 (TSP-1), a matricellular protein released in abundance from activated platelets and accumulated in sites of vascular injury, as a regulator of CAM expression. TSP-1 induced expression of VCAM-1 and ICAM-1 on endothelium of various origins, which in turn, resulted in a significant increase of monocyte attachment. This effect could be mimicked by a peptide derived from the C-terminal domain of TSP-1 and known to interact with CD47 on the cell surface. The essential role of CD47 in the cellular responses to TSP-1 was demonstrated further using inhibitory antibodies and knockdown of CD47 with small interfering RNA. Furthermore, we demonstrated that secretion of endogenous TSP-1 and its interaction with CD47 on the cell surface mediates endothelial response to the major proinflammatory agent, tumor necrosis factor α (TNF-α). Taken together, this study identifies a novel mechanism regulating CAM expression and subsequent monocyte binding to endothelium, which might influence the development of anti-atherosclerosis therapeutic strategies. PMID:15833768

  10. Chinese Herbal Cardiotonic Pill Stabilizes Vulnerable Plaques in Rabbits by Decreasing the Expression of Adhesion Molecules

    PubMed Central

    Chen, Liang; Li, Xiaonan; Li, Changjiang; Rong, Yuanyuan; Xiao, Yawei; Xu, Xinsheng; Yao, Guihua; Jiang, Guihua

    2016-01-01

    Abstract: The cardiotonic pill (CP), consisting of a mixture of Radix Salviae Miltiorrhizae, Radix Notoginseng, and Borneolum Syntheticum, has been widely used in the prevention and treatment of cardiovascular disease. Adhesion molecules, including intercellular cell adhesion molecule-1 and vascular cell adhesion molecule-1, are involved in the development of vulnerable plaque. We investigated the effect of the CP in a rabbit model of vulnerable plaque established by local transfection with p53 gene. Compared with the control group, rabbits with vulnerable plaque showed a significantly lower intima-media thickness and plaque burden after CP treatment for 12 weeks. Moreover, the reduction in rate of plaque rupture and vulnerability index was similar. On enzyme-linked immunosorbent assay, real-time polymerase chain reaction, and immunohistochemistry analysis, the expression of intercellular cell adhesion molecule-1 and vascular cell adhesion molecule-1 was inhibited with CP treatment. CP treatment could postpone atherosclerotic plaque development and stabilize vulnerable plaque by inhibiting the expression of adhesion molecules in treatment of cardiovascular disease. PMID:27110743

  11. Inducible expression of vascular cell adhesion molecule-1 by vascular smooth muscle cells in vitro and within rabbit atheroma.

    PubMed Central

    Li, H.; Cybulsky, M. I.; Gimbrone, M. A.; Libby, P.

    1993-01-01

    Vascular cell adhesion molecule-1 (VCAM-1), a mononuclear leukocyte adhesion molecule, is expressed in cultured vascular endothelial cells activated by cytokines and is induced in rabbit aortic endothelium in vivo within 1 week after initiation of an atherogenic diet. We now demonstrate that vascular smooth muscle cells can also express VCAM-1 in rabbit atherosclerotic lesions in vivo and in response to cytokines in vitro. Immunohistochemical staining of aortas from rabbits fed a 0.3% cholesterol-containing diet revealed that a portion of smooth muscle cells within intimal foam cell-rich lesions expressed VCAM-1. The intimal VCAM-1-expressing cells localized predominantly in regions above the internal elastic lamina. These VCAM-1-positive cells had the typical spindle shape of smooth muscle cells but had reduced alpha-actin expression in comparison to normal medial smooth muscle cells, and did not bear markers for endothelium, macrophages, and T cells. In culture, rabbit aortic smooth muscle cells expressed VCAM-1 mRNA and protein in a time- and concentration-dependent fashion when exposed to interferon-gamma or Gram-negative bacterial lipopolysaccharide. Cultured human vascular smooth muscle cells also expressed VCAM-1 mRNA and protein in response to lipopolysaccharide, interferon-gamma, and interleukin-4. The monokines interleukin-1 alpha and tumor necrosis factor-alpha did not induce VCAM-1 expression in either rabbit or human vascular smooth muscle cells. Inducible VCAM-1 expression by vascular smooth muscle cells in vivo during hypercholesterolemia and in vitro in response to certain cytokines suggests a broader range of VCAM-1 functions in vascular biology than heretofore appreciated. Images Figure 1 Figure 2 Figure 3 Figure 4 PMID:7504883

  12. Protein adhesion on dental surfaces-a combined surface analytical approach.

    PubMed

    Müller, Christine; Wald, Johanna; Hoth-Hannig, Wiebke; Umanskaya, Natalia; Scholz, Daniel; Hannig, Matthias; Ziegler, Christiane

    2011-05-01

    Protein adsorption is a field of huge interest in a number of application fields. Information on protein adhesion is accessible by a variety of methods. However, the results obtained are significantly influenced by the applied technique. The objective of this work was to understand the role of adhesion forces (obtained by scanning force spectroscopy, SFS) in the process of protein adsorption and desorption. In SFS, the protein is forced to and retracted from the surface, even under unfavorable conditions, in contrast to the natural situation. Furthermore, adhesion forces are correlated with adhesion energies, neglecting the entropic part in the Gibbs enthalpy. In this context, dynamic contact angle (DCA) measurements were performed to identify the potential of this method to complement SFS data. In DCA measurements, the protein diffuses voluntarily to the surface and information on surface coverage and reversibility of adsorption is obtained, including entropic effects (conformational changes and hydrophobic effect). It could be shown that the surface coverage (by DCA) of bovine serum albumin on dental materials correlates well with the adhesion forces (by SFS) if no hydrophobic surface is involved. On those, the entropic hydrophobic effect plays a major role. As a second task, the reversibility of the protein adsorption, i.e., the voluntary desorption as studied by DCA, was compared to the adhesion forces. Here, a correlation between low adhesion forces and good reversibility could be found as long as no covalent bonds were involved. The comparative study of DCA and SFS, thus, leads to a more detailed picture of the complete adsorption/desorption cycle.

  13. Mispolarization of desmosomal proteins and altered intercellular adhesion in autosomal dominant polycystic kidney disease.

    PubMed

    Silberberg, Melina; Charron, Audra J; Bacallao, Robert; Wandinger-Ness, Angela

    2005-06-01

    Polycystin-1, the product of the major gene mutated in autosomal dominant polycystic kidney disease (ADPKD), has been shown to associate with multiple epithelial cell junctions. Our hypothesis is that polycystin-1 is an important protein for the initial establishment of cell-cell junctions and maturation of the cell and that polycystin-1 localization is dependent on the degree of cell polarization. Using laser-scanning confocal microscopy and two models of cell polarization, polycystin-1 and desmosomes were found to colocalize during the initial establishment of cell-cell contact when junctions were forming. However, colocalization was lost in confluent monolayers. Parallel morphological and biochemical evaluations revealed a profound mispolarization of desmosomal components to both the apical and basolateral domains in primary ADPKD cells and tissue. Studies of the intermediate filament network associated with desmosomes showed that there is a decrease in cytokeratin levels and an abnormal expression of the mesenchymal protein vimentin in the disease. Moreover, we show for the first time that the structural alterations seen in adherens and desmosomal junctions have a functional impact, leaving the ADPKD cells with weakened cell-cell adhesion. In conclusion, in this paper we show that polycystin-1 transiently colocalizes with desmosomes and that desmosomal proteins are mislocalized as a consequence of polycystin-1 mutation.

  14. Proteomic dataset of the sea urchin Paracentrotus lividus adhesive organs and secreted adhesive

    PubMed Central

    Lebesgue, Nicolas; da Costa, Gonçalo; Ribeiro, Raquel Mesquita; Ribeiro-Silva, Cristina; Martins, Gabriel G.; Matranga, Valeria; Scholten, Arjen; Cordeiro, Carlos; Heck, Albert J.R.; Santos, Romana

    2016-01-01

    Sea urchins have specialized adhesive organs called tube feet, which mediate strong but reversible adhesion. Tube feet are composed by a disc, producing adhesive and de-adhesive secretions for substratum attachment, and a stem for movement. After detachment the secreted adhesive remains bound to the substratum as a footprint. Recently, a label-free quantitative proteomic approach coupled with the latest mass-spectrometry technology was used to analyze the differential proteome of Paracentrotus lividus adhesive organ, comparing protein expression levels in the tube feet adhesive part (the disc) versus the non-adhesive part (the stem), and also to profile the proteome of the secreted adhesive (glue). This data article contains complementary figures and results related to the research article “Deciphering the molecular mechanisms underlying sea urchin reversible adhesion: a quantitative proteomics approach” (Lebesgue et al., 2016) [1]. Here we provide a dataset of 1384 non-redundant proteins, their fragmented peptides and expression levels, resultant from the analysis of the tube feet differential proteome. Of these, 163 highly over-expressed tube feet disc proteins (>3-fold), likely representing the most relevant proteins for sea urchin reversible adhesion, were further annotated in order to determine the potential functions. In addition, we provide a dataset of 611 non-redundant proteins identified in the secreted adhesive proteome, as well as their functional annotation and grouping in 5 major protein groups related with adhesive exocytosis, and microbial protection. This list was further analyzed to identify the most abundant protein groups and pinpoint putative adhesive proteins, such as Nectin, the most abundant adhesive protein in sea urchin glue. The obtained data uncover the key proteins involved in sea urchins reversible adhesion, representing a step forward to the development of new wet-effective bio-inspired adhesives. PMID:27182547

  15. Proteomic dataset of the sea urchin Paracentrotus lividus adhesive organs and secreted adhesive.

    PubMed

    Lebesgue, Nicolas; da Costa, Gonçalo; Ribeiro, Raquel Mesquita; Ribeiro-Silva, Cristina; Martins, Gabriel G; Matranga, Valeria; Scholten, Arjen; Cordeiro, Carlos; Heck, Albert J R; Santos, Romana

    2016-06-01

    Sea urchins have specialized adhesive organs called tube feet, which mediate strong but reversible adhesion. Tube feet are composed by a disc, producing adhesive and de-adhesive secretions for substratum attachment, and a stem for movement. After detachment the secreted adhesive remains bound to the substratum as a footprint. Recently, a label-free quantitative proteomic approach coupled with the latest mass-spectrometry technology was used to analyze the differential proteome of Paracentrotus lividus adhesive organ, comparing protein expression levels in the tube feet adhesive part (the disc) versus the non-adhesive part (the stem), and also to profile the proteome of the secreted adhesive (glue). This data article contains complementary figures and results related to the research article "Deciphering the molecular mechanisms underlying sea urchin reversible adhesion: a quantitative proteomics approach" (Lebesgue et al., 2016) [1]. Here we provide a dataset of 1384 non-redundant proteins, their fragmented peptides and expression levels, resultant from the analysis of the tube feet differential proteome. Of these, 163 highly over-expressed tube feet disc proteins (>3-fold), likely representing the most relevant proteins for sea urchin reversible adhesion, were further annotated in order to determine the potential functions. In addition, we provide a dataset of 611 non-redundant proteins identified in the secreted adhesive proteome, as well as their functional annotation and grouping in 5 major protein groups related with adhesive exocytosis, and microbial protection. This list was further analyzed to identify the most abundant protein groups and pinpoint putative adhesive proteins, such as Nectin, the most abundant adhesive protein in sea urchin glue. The obtained data uncover the key proteins involved in sea urchins reversible adhesion, representing a step forward to the development of new wet-effective bio-inspired adhesives.

  16. Both protein kinase A and exchange protein activated by cAMP coordinate adhesion of human vascular endothelial cells.

    PubMed

    Netherton, Stuart J; Sutton, Jayda A; Wilson, Lindsay S; Carter, Rhonda L; Maurice, Donald H

    2007-10-12

    cAMP regulates integrin-dependent adhesions of vascular endothelial cells (VECs) to extracellular matrix proteins, their vascular endothelial cadherin-dependent intercellular adhesions, and their proliferation and migration in response to growth and chemotactic factors. Previously, we reported that cAMP-elevating agents differentially inhibited migration of human VECs isolated from large vascular structures (macro-VECs, human aortic endothelial cells [HAECs]) or small vascular structures (micro-VECs, human microvascular endothelial cells [HMVECs]) and that cAMP hydrolysis by phosphodiesterase (PDE)3 and PDE4 enzymes was important in coordinating this difference. Here we report that 2 cAMP-effector enzymes, namely protein kinase (PK)A and exchange protein activated by cAMP (EPAC), each regulate extracellular matrix protein-based adhesions of both macro- and micro-VECs. Of interest and potential therapeutic importance, we report that although specific pharmacological activation of EPAC markedly stimulated adhesion of micro-VECs to extracellular matrix proteins when PKA was inhibited, this treatment only modestly promoted adhesion of macro-VECs. Consistent with an important role for cAMP PDEs in this difference, PDE3 or PDE4 inhibitors promoted EPAC-dependent adhesions in micro-VECs when PKA was inhibited but not in macro-VECs. At a molecular level, we identify multiple, nonoverlapping, PKA- or EPAC-based signaling protein complexes in both macro- and micro-VECs and demonstrate that each of these complexes contains either PDE3B or PDE4D but not both of these PDEs. Taken together, our data support the concept that adhesion of macro- and micro-VECs is differentially regulated by cAMP and that these differences are coordinated through selective actions of cAMP at multiple nonoverlapping signaling complexes that contain PKA or EPAC and distinct PDE variants.

  17. SDF-1-induced adhesion of monocytes to vascular endothelium is modulated by azelnidipine via protein kinase C inhibition.

    PubMed

    Takahashi, Keiko; Shimokado, Kentaro; Yoshida, Masayuki

    2006-12-15

    Monocyte-endothelial interaction and its modulation by chemokines play a key role in atherogenesis and inflammation. We examined the potential effects of stromal cell-derived factor (SDF-1) and azelnidipine, a novel dihydropyridine derivative, toward monocyte-endothelial interaction. Human monocytes were prepared from peripheral blood mononuclear cells obtained from healthy volunteers and pretreated with azelnidipine (1 microM) for 48 h, after which their adhesion to interleukin-1beta (IL-1beta)-activated human umbilical vein endothelial cells (HUVECs) was analyzed using an in vitro flow apparatus with a shear stress of 1 dyn/cm(2). In some experiments, monocytes were incubated in the presence of stromal cell-derived factor (SDF-1), a chemokine, just prior to the assay. Pre-incubation of monocytes with SDF-1 enhanced their adhesion to activated HUVECs. When monocytes were pre-incubated in the presence of azelnidipine, baseline levels as well as SDF-1-induced monocyte adhesion levels were reduced. Interestingly, the surface expressions of the adhesion molecules CD11a, CD11b, and CD36, were not changed by azelnidipine treatment. Western blotting analysis revealed that activation of protein kinase C (PKC)alpha was inhibited by azelnidipine treatment, while it also reduced the SDF-1-induced increase in intracellular calcium concentration ([Ca(2+)](i)). Further, pre-incubation of monocytes with Go6976, a potent inhibitor of PKCalpha, significantly reduced monocyte adhesion to HUVECs. Our results demonstrated an inhibitory action of azelnidipine toward adhesive interactions of monocytes to HUVECs, which involves inhibition of PKCalpha and a reduction in [Ca(2+)](i). These findings imply a protective role of azelnidipine against inflammation in atherosclerosis.

  18. Biofilm-forming Staphylococcus epidermidis expressing vancomycin resistance early after adhesion to a metal surface.

    PubMed

    Sakimura, Toshiyuki; Kajiyama, Shiro; Adachi, Shinji; Chiba, Ko; Yonekura, Akihiko; Tomita, Masato; Koseki, Hironobu; Miyamoto, Takashi; Tsurumoto, Toshiyuki; Osaki, Makoto

    2015-01-01

    We investigated biofilm formation and time of vancomycin (VCM) resistance expression after adhesion to a metal surface in Staphylococcus epidermidis. Biofilm-forming Staphylococcus epidermidis with a VCM MIC of 1 μg/mL was used. The bacteria were made to adhere to a stainless steel washer and treated with VCM at different times and concentrations. VCM was administered 0, 2, 4, and 8 hours after adhesion. The amount of biofilm formed was evaluated based on the biofilm coverage rates (BCRs) before and after VCM administration, bacterial viability in biofilm was visually observed using the fluorescence staining method, and the viable bacterial count in biofilm was measured. The VCM concentration required to decrease BCR significantly compared with that of VCM-untreated bacteria was 4 μg/mL, even in the 0 hr group. In the 4 and 8 hr groups, VCM could not inhibit biofilm growth even at 1,024 μg/mL. In the 8 hr group, viable bacteria remained in biofilm at a count of 10(4) CFU even at a high VCM concentration (1,024 μg/mL). It was suggested that biofilm-forming Staphylococcus epidermidis expresses resistance to VCM early after adhesion to a metal surface. Resistance increased over time after adhesion as the biofilm formed, and strong resistance was expressed 4-8 hours after adhesion.

  19. Insights into the Utility of the Focal Adhesion Scaffolding Proteins in the Anaerobic Fungus Orpinomyces sp. C1A

    PubMed Central

    Calkins, Shelby; Youssef, Noha H.

    2016-01-01

    Focal adhesions (FAs) are large eukaryotic multiprotein complexes that are present in all metazoan cells and function as stable sites of tight adhesion between the extracellular matrix (ECM) and the cell’s cytoskeleton. FAs consist of anchor membrane protein (integrins), scaffolding proteins (e.g. α-actinin, talin, paxillin, and vinculin), signaling proteins of the IPP complex (e.g. integrin-linked kinase, α-parvin, and PINCH), and signaling kinases (e.g. focal adhesion kinase (FAK) and Src kinase). While genes encoding complete focal adhesion machineries are present in genomes of all multicellular Metazoa; incomplete machineries were identified in the genomes of multiple non-metazoan unicellular Holozoa, basal fungal lineages, and amoebozoan representatives. Since a complete FA machinery is required for functioning, the putative role, if any, of these incomplete FA machineries is currently unclear. We sought to examine the expression patterns of FA-associated genes in the anaerobic basal fungal isolate Orpinomyces sp. strain C1A under different growth conditions and at different developmental stages. Strain C1A lacks clear homologues of integrin, and the two signaling kinases FAK and Src, but encodes for all scaffolding proteins, and the IPP complex proteins. We developed a protocol for synchronizing growth of C1A cultures, allowing for the collection and mRNA extraction from flagellated spores, encysted germinating spores, active zoosporangia, and late inactive sporangia of strain C1A. We demonstrate that the genes encoding the FA scaffolding proteins α-actinin, talin, paxillin, and vinculin are indeed transcribed under all growth conditions, and at all developmental stages of growth. Further, analysis of the observed transcriptional patterns suggests the putative involvement of these components in alternative non-adhesion-specific functions, such as hyphal tip growth during germination and flagellar assembly during zoosporogenesis. Based on these results

  20. A Role for the Protein Tyrosine Phosphatase CD45 in Macrophage Adhesion through the Regulation of Paxillin Degradation

    PubMed Central

    St-Pierre, Joëlle; Ostergaard, Hanne L.

    2013-01-01

    CD45 is a protein tyrosine phosphatase expressed on all cells of hematopoietic origin that is known to regulate Src family kinases. In macrophages, the absence of CD45 has been linked to defects in adhesion, however the molecular mechanisms involved remain poorly defined. In this study, we show that bone marrow derived macrophages from CD45-deficient mice exhibit abnormal cell morphology and defective motility. These defects are accompanied by substantially decreased levels of the cytoskeletal-associated protein paxillin, without affecting the levels of other proteins. Degradation of paxillin in CD45-deficient macrophages is calpain-mediated, as treatment with a calpain inhibitor restores paxillin levels in these cells and enhances cell spreading. Inhibition of the tyrosine kinases proline-rich tyrosine kinase (Pyk2) and focal adhesion kinase (FAK), kinases that are capable of mediating tyrosine phosphorylation of paxillin, also restored paxillin levels, indicating a role for these kinases in the CD45-dependent regulation of paxillin. These data demonstrate that CD45 functions to regulate Pyk2/FAK activity, likely through the activity of Src family kinases, which in turn regulates the levels of paxillin to modulate macrophage adhesion and migration. PMID:23936270

  1. Exosomes from iPSCs Delivering siRNA Attenuate Intracellular Adhesion Molecule-1 Expression and Neutrophils Adhesion in Pulmonary Microvascular Endothelial Cells.

    PubMed

    Ju, Zhihai; Ma, Jinhui; Wang, Chen; Yu, Jie; Qiao, Yeru; Hei, Feilong

    2017-04-01

    The pro-inflammatory activation of pulmonary microvascular endothelial cells resulting in continuous expression of cellular adhesion molecules, and subsequently recruiting primed neutrophils to form a firm neutrophils-endothelium (PMN-EC) adhesion, has been examined and found to play a vital role in acute lung injury (ALI). RNA interference (RNAi) is a cellular process through harnessing a natural pathway silencing target gene based on recognition and subsequent degradation of specific mRNA sequences. It opens a promising approach for precision medicine. However, this application was hampered by many obstacles, such as immunogenicity, instability, toxicity problems, and difficulty in across the biological membrane. In this study, we reprogrammed urine exfoliated renal epithelial cells into human induced pluripotent stem cells (huiPSCs) and purified the exosomes (Exo) from huiPSCs as RNAi delivery system. Through choosing the episomal system to deliver transcription factors, we obtained a non-integrating huiPSCs. Experiments in both vitro and vivo demonstrated that these huiPSCs possess the pluripotent properties. The exosomes of huiPSCs isolated by differential centrifugation were visualized by transmission electron microscopy (TEM) showing a typical exosomal appearance with an average diameter of 122 nm. Immunoblotting confirmed the presence of the typical exosomal markers, including CD63, TSG 101, and Alix. Co-cultured PKH26-labeled exosomes with human primary pulmonary microvascular endothelial cells (HMVECs) confirmed that they could be internalized by recipient cells at a time-dependent manner. Then, electroporation was used to introduce siRNA against intercellular adhesion molecule-1 (ICAM-1) into exosomes to form an Exo/siRNA compound. The Exo/siRNA compound efficiently delivered the target siRNA into HMVECs causing selective gene silencing, inhibiting the ICAM-1 protein expression, and PMN-EC adhesion induced by lipopolysaccharide (LPS). These data suggest

  2. Spatio-Temporally Restricted Expression of Cell Adhesion Molecules during Chicken Embryonic Development

    PubMed Central

    Roy, Priti; Bandyopadhyay, Amitabha

    2014-01-01

    Differential cell adhesive properties are known to regulate important developmental events like cell sorting and cell migration. Cadherins and protocadherins are known to mediate these cellular properties. Though a large number of such molecules have been predicted, their characterization in terms of interactive properties and cellular roles is far from being comprehensive. To narrow down the tissue context and collect correlative evidence for tissue specific roles of these molecules, we have carried out whole-mount in situ hybridization based RNA expression study for seven cadherins and four protocadherins. In developing chicken embryos (HH stages 18, 22, 26 and 28) cadherins and protocadherins are expressed in tissue restricted manner. This expression study elucidates precise expression domains of cell adhesion molecules in the context of developing embryos. These expression domains provide spatio-temporal context in which the function of these genes can be further explored. PMID:24806091

  3. Inhibitor of DASH proteases affects expression of adhesion molecules in osteoclasts and reduces myeloma growth and bone disease.

    PubMed

    Pennisi, Angela; Li, Xin; Ling, Wen; Khan, Sharmin; Gaddy, Dana; Suva, Larry J; Barlogie, Bart; Shaughnessy, John D; Aziz, Nazneen; Yaccoby, Shmuel

    2009-06-01

    Dipeptidyl peptidase (DPP) IV activity and/or structure homologues (DASH) are serine proteases implicated in tumourigenesis. We previously found that a DASH protease, fibroblast activation protein (FAP), was involved in osteoclast-induced myeloma growth. Here we further demonstrated expression of various adhesion molecules in osteoclasts cultured alone or cocultured with myeloma cells, and tested the effects of DASH inhibitor, PT-100, on myeloma cell growth, bone disease, osteoclast differentiation and activity, and expression of adhesion molecules in osteoclasts. PT-100 had no direct effects on viability of myeloma cells or mature osteoclasts, but significantly reduced survival of myeloma cells cocultured with osteoclasts. Real-time PCR array for 85 adhesion molecules revealed upregulation of 17 genes in osteoclasts after coculture with myeloma cells. Treatment of myeloma/osteoclast cocultures with PT-100 significantly downregulated 18 of 85 tested genes in osteoclasts, some of which are known to play roles in tumourigenesis and osteoclastogenesis. PT-100 also inhibited osteoclast differentiation and subsequent pit formation. Resorption activity of mature osteoclasts and differentiation of osteoblasts were not affected by PT-100. In primary myelomatous severe combined immunodeficient (SCID)-hu mice PT-100 reduced osteoclast activity, bone resorption and tumour burden. These data demonstrated that DASH proteases are involved in myeloma bone disease and tumour growth.

  4. Binding of the cell adhesive protein tropoelastin to PTFE through plasma immersion ion implantation treatment.

    PubMed

    Bax, Daniel V; Wang, Yiwei; Li, Zhe; Maitz, Peter K M; McKenzie, David R; Bilek, Marcela M M; Weiss, Anthony S

    2011-08-01

    The interaction of proteins and cells with polymers is critical to their use in scientific and medical applications. In this study, plasma immersion ion implantation (PIII) was used to modify the surface of polytetrafluorethylene (PTFE), enabling the covalent binding of a cell adhesive protein, tropoelastin, without employing chemical linking molecules. Tropoelastin coating of untreated or PIII treated PFTE simultaneously promoted and blocked cell interactions respectively, i.e. PIII treatment of the PTFE surface completely inverses the cell interactive properties of bound tropoelastin. This activity persisted over long term storage of the PIII treated surfaces. The integrin binding C-terminus of tropoelastin was markedly less solvent exposed when bound to PIII treated PTFE than untreated PTFE, accounting for the modulation of cell adhesive activity. This presents a new methodology to specifically modulate cell behavior on a polymer surface using a simple one step treatment process, by adjusting the adhesive activity of a single extracellular matrix protein.

  5. Recent approaches in designing bioadhesive materials inspired by mussel adhesive protein

    PubMed Central

    Kord Forooshani, Pegah

    2016-01-01

    ABSTRACT Marine mussels secret protein‐based adhesives, which enable them to anchor to various surfaces in a saline, intertidal zone. Mussel foot proteins (Mfps) contain a large abundance of a unique, catecholic amino acid, Dopa, in their protein sequences. Catechol offers robust and durable adhesion to various substrate surfaces and contributes to the curing of the adhesive plaques. In this article, we review the unique features and the key functionalities of Mfps, catechol chemistry, and strategies for preparing catechol‐functionalized polymers. Specifically, we reviewed recent findings on the contributions of various features of Mfps on interfacial binding, which include coacervate formation, surface drying properties, control of the oxidation state of catechol, among other features. We also summarized recent developments in designing advanced biomimetic materials including coacervate‐forming adhesives, mechanically improved nano‐ and micro‐composite adhesive hydrogels, as well as smart and self‐healing materials. Finally, we review the applications of catechol‐functionalized materials for the use as biomedical adhesives, therapeutic applications, and antifouling coatings. © 2016 The Authors. Journal of Polymer Science Part A: Polymer Chemistry Published by Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2017, 55, 9–33 PMID:27917020

  6. Single Adhesive Nanofibers from a Live Diatom Have the Signature Fingerprint of Modular Proteins

    PubMed Central

    Dugdale, T. M.; Dagastine, R.; Chiovitti, A.; Mulvaney, P.; Wetherbee, R.

    2005-01-01

    The adhesive and mechanical properties of a cell-substratum adhesive secreted by live diatom cells were examined in situ using atomic force microscopy. The resulting force curves have a regular saw-tooth pattern, the characteristic fingerprint of modular proteins, and when bridged between tip and surface can repeatedly be stretched and relaxed resulting in precisely overlaying saw-tooth curves (up to ∼600 successive cycles). The average rupture force of the peaks is 0.794 ± 0.007 (mean ± SE) nN at a loading rate of 0.8 μm/s and the average persistence length is 0.026 ± <0.001 (mean ± SE) nm (fit using the worm-like chain model). We propose that we are pulling on single adhesive nanofibers, each a cohesive unit composed of a set number of modular proteins aligned in register. Furthermore, we can observe and differentiate when up to three adhesive nanofibers are pulled based upon multimodal distributions of force and persistence length. The high force required for bond rupture, high extensibility (∼1.2 μm), and the accurate and rapid refolding upon relaxation, together provide strong and flexible properties ideally suited for the cell-substratum adhesion of this fouling diatom and allow us to understand the mechanism responsible for the strength of adhesion. PMID:16169972

  7. Chronic restraint stress down-regulates amygdaloid expression of polysialylated neural cell adhesion molecule.

    PubMed

    Cordero, M I; Rodríguez, J J; Davies, H A; Peddie, C J; Sandi, C; Stewart, M G

    2005-01-01

    The amygdala is a brain area which plays a decisive role in fear and anxiety. Since exposure to chronic stress can induce profound effects in emotion and cognition, plasticity in specific amygdaloid nuclei in response to prior stress has been hypothesized to account for stress-induced emotional alterations. In order to identify amygdala nuclei which may be affected under chronic stress conditions we evaluated the effects of 21-days chronic restraint stress on the expression of a molecule implicated crucially in alterations in structural plasticity: the polysialylated neural cell adhesion molecule. We found that polysialylated neural cell adhesion molecule-immunoreactivity within the amygdala, present in somata and neuronal processes, has a regional gradient with the central medial and medial amygdaloid nuclei showing the highest levels. Our results demonstrate that chronic restraint stress induced an overall reduction in polysialylated neural cell adhesion molecule-immunoreactivity in the amygdaloid complex, mainly due to a significant decrease in the central medial amygdaloid and medial amygdaloid nuclei. Our data suggest that polysialylated neural cell adhesion molecule in these nuclei may play a prominent role in functional and structural remodeling induced by stress, being a potential mechanism for cognitive and emotional modulation. Furthermore, these finding provide the first clear evidence that life experiences can regulate the expression of polysialylated neural cell adhesion molecule in the amygdaloid complex.

  8. Hydrogen-Rich Medium Attenuated Lipopolysaccharide-Induced Monocyte-Endothelial Cell Adhesion and Vascular Endothelial Permeability via Rho-Associated Coiled-Coil Protein Kinase.

    PubMed

    Xie, Keliang; Wang, Weina; Chen, Hongguang; Han, Huanzhi; Liu, Daquan; Wang, Guolin; Yu, Yonghao

    2015-07-01

    Sepsis is the leading cause of death in critically ill patients. In recent years, molecular hydrogen, as an effective free radical scavenger, has been shown a selective antioxidant and anti-inflammatory effect, and it is beneficial in the treatment of sepsis. Rho-associated coiled-coil protein kinase (ROCK) participates in junction between normal cells, and regulates vascular endothelial permeability. In this study, we used lipopolysaccharide to stimulate vascular endothelial cells and explored the effects of hydrogen-rich medium on the regulation of adhesion of monocytes to endothelial cells and vascular endothelial permeability. We found that hydrogen-rich medium could inhibit adhesion of monocytes to endothelial cells and decrease levels of adhesion molecules, whereas the levels of transepithelial/endothelial electrical resistance values and the expression of vascular endothelial cadherin were increased after hydrogen-rich medium treatment. Moreover, hydrogen-rich medium could lessen the expression of ROCK, as a similar effect of its inhibitor Y-27632. In addition, hydrogen-rich medium could also inhibit adhesion of polymorphonuclear neutrophils to endothelial cells. In conclusion, hydrogen-rich medium could regulate adhesion of monocytes/polymorphonuclear neutrophils to endothelial cells and vascular endothelial permeability, and this effect might be related to the decreased expression of ROCK protein.

  9. Hydrophobic enhancement of Dopa-mediated adhesion in a mussel foot protein

    PubMed Central

    Wei, Wei; Yu, Jing; Broomell, Christopher; Israelachvili, Jacob N.; Waite, J. Herbert

    2013-01-01

    Dopa (3,4-dihydroxyphenylalanine) is recognized as a key chemical signature of mussel adhesion and has been adopted into diverse synthetic polymer systems. Dopa’s notorious susceptibility to oxidation, however, poses significant challenges to the practical translation of mussel adhesion. Using a Surface Forces Apparatus to investigate the adhesion of Mfp3 (mussel foot protein 3) slow, a hydrophobic protein variant of the Mfp3 family in the plaque, we have discovered a subtle molecular strategy correlated with hydrophobicity that appears to compensate for Dopa instability. At pH 3, where Dopa is stable, Mfp3 slow like Mfp3 fast adhesion to mica is directly proportional to the mol% of Dopa present in the protein. At pH 5.5 and 7.5, however, loss of adhesion in Mfp3 slow was less than half that occurring in Mfp3 fast, purportedly because Dopa in Mfp3 slow is less prone to oxidation. Indeed, cyclic voltammetry showed that the oxidation potential of Dopa in Mfp3 slow is significantly higher than in Mfp3 fast at pH 7.5. A much greater difference between the two variants was revealed in the interaction energy of two symmetric Mfp3 slow films (Ead = −3 mJ/m2). This energy corresponds to the energy of protein cohesion which is notable for its reversibility and pH-independence. Exploitation of aromatic hydrophobic sequences to protect Dopa against oxidation as well as to mediate hydrophobic and H-bonding interactions between proteins provides new insights for developing effective artificial underwater adhesives. PMID:23214725

  10. Hydrophobic enhancement of Dopa-mediated adhesion in a mussel foot protein.

    PubMed

    Wei, Wei; Yu, Jing; Broomell, Christopher; Israelachvili, Jacob N; Waite, J Herbert

    2013-01-09

    Dopa (3,4-dihydroxyphenylalanine) is recognized as a key chemical signature of mussel adhesion and has been adopted into diverse synthetic polymer systems. Dopa's notorious susceptibility to oxidation, however, poses significant challenges to the practical translation of mussel adhesion. Using a surface forces apparatus to investigate the adhesion of mussel foot protein 3 (Mfp3) "slow", a hydrophobic protein variant of the Mfp3 family in the plaque, we have discovered a subtle molecular strategy correlated with hydrophobicity that appears to compensate for Dopa instability. At pH 3, where Dopa is stable, Mfp3 slow, like Mfp3 "fast" adhesion to mica, is directly proportional to the mol % of Dopa present in the protein. At pH of 5.5 and 7.5, however, loss of adhesion in Mfp3 slow was less than half that occurring in Mfp3 fast, purportedly because Dopa in Mfp3 slow is less prone to oxidation. Indeed, cyclic voltammetry showed that the oxidation potential of Dopa in Mfp3 slow is significantly higher than in Mfp3 fast at pH of 7.5. A much greater difference between the two variants was revealed in the interaction energy of two symmetric Mfp3 slow films (E(ad) = -3 mJ/m(2)). This energy corresponds to the energy of protein cohesion which is notable for its reversibility and pH independence. Exploitation of aromatic hydrophobic sequences to protect Dopa against oxidation as well as to mediate hydrophobic and H-bonding interactions between proteins provides new insights for developing effective artificial underwater adhesives.

  11. Proinflammatory stimuli regulate endothelial hyaluronan expression and CD44/HA-dependent primary adhesion.

    PubMed Central

    Mohamadzadeh, M; DeGrendele, H; Arizpe, H; Estess, P; Siegelman, M

    1998-01-01

    The localization of circulating leukocytes within inflamed tissues occurs as the result of interactions with and migration across vascular endothelium, and is governed, in part, by the expression of adhesion molecules on both cell types. Recently, we have described a novel primary adhesion interaction between the structurally activated form of the adhesion molecule CD44 on lymphocytes and its major ligand hyaluronan on endothelial cells under physiologic laminar flow conditions, and have proposed that this interaction functions in an extravasation pathway for lymphocytes in vascular beds at sites of inflammation. While the regulation of activated CD44 on leukocytes has been characterized in depth, regulation of hyaluronate (HA) on endothelial cells has not been extensively studied. Here we demonstrate that the expression of HA on cultured endothelial cell lines and primary endothelial cultures is inducible by the proinflammatory cytokines TNFalpha and IL-1beta, as well as bacterial lipopolysaccharide. In addition, this inducibility appears strikingly restricted to endothelial cells derived from microvascular, but not large vessel, sources. The elevated HA levels thus induced result in increased CD44-dependent adhesive interactions in both nonstatic shear and laminar flow adhesion assays. Changes in mRNA levels for the described HA synthetic and degradative enzymes were not found, suggesting other more complex mechanisms of regulation. Together, these data add to the selectin and immunoglobulin gene families a new inducible endothelial adhesive molecule, hyaluronan, and help to further our understanding of the potential physiologic roles of the CD44/HA interaction; i.e., local cytokine production within inflamed vascular beds may enhance surface hyaluronan expression on endothelial cells, thereby creating local sites receptive to the CD44/HA interaction and thus extravasation of inflammatory cells. PMID:9421471

  12. Adhesion dynamics of porcine esophageal fibroblasts on extracellular matrix protein-functionalized poly(lactic acid).

    PubMed

    Cai, Ning; Gong, Yingxue; Chian, Kerm Sin; Chan, Vincent; Liao, Kin

    2008-03-01

    Effective attachment of esophageal cells on biomaterials is one important requirement in designing engineered esophagus substitute for esophageal cancer treatment. In this study, poly(lactic acid) (PLA) was subjected to surface modification by coupling extracellular matrix (ECM) proteins on its surface to promote cell adhesion. Two typical ECM proteins, collagen type I (COL) and fibronectin (FN), were immobilized on the PLA surface with the aid of glutaraldehyde as a cross linker between aminolyzed PLA and ECM proteins. By using confocal reflectance interference contrast microscopy (C-RICM) integrating with phase contrast microscopy, the long-term adhesion dynamics of porcine esophageal fibroblasts (PEFs) on four types of surfaces (unmodified PLA, PLA-COOH, PLA-COL and PLA-FN) was investigated during 24 h of culture. It is demonstrated by C-RICM results that PEFs form strong adhesion contact on all four types of surfaces at different stages of cell seeding. Among the four surfaces, PEFs on the PLA-FN surface reach the maximum adhesion energy (9.5 x 10(-7) J m(-2)) in the shortest time (20 min) during the initial stage of cell seeding. After adhesion energy reaches the maximum value, PEFs maintain their highly deformed geometries till they reached a steady state after 20 h of culture. F-actin immunostaining results show that the evolvement of spatial organization of F-actin is tightly correlated with the formation of adhesion contact and cell spreading. Furthermore, the cell attachment ratio of PEFs on PLA in 2 h is only 26% compared with 88% on PLA-FN, 73% on PLA-COL and 36% on PLA-COOH. All the results demonstrate the effect of surface functionalization on the biophysical responses of PEFs in cell adhesion. Fibronectin-immobilized PLA demonstrates promising potential for application as an engineered esophagus substitute.

  13. Expression of leukocyte-endothelial cell adhesion molecules on monocyte adhesion to human endothelial cells on plasma treated PET and PTFE in vitro.

    PubMed

    Pu, F R; Williams, R L; Markkula, T K; Hunt, J A

    2002-12-01

    We used a coculture model to evaluate the inflammatory potential of ammonia gas plasma modified PET and PTFE by flow cytometry and immunohistochemistry. In these studies, human endothelial cells from umbilical cord (HUVEC) and promonocytic U937 cells were used. HUVECs grown on polystyrene tissue culture coverslips and HUVECs stimulated with tumour necrosis factor (TNF-alpha) were used as controls. U937 adhesion to endothelium on each surface was evaluated at day 1 and day 7. To further investigate the role of leukocyte-endothelial cell adhesion molecules (CAMs) in cell-to-cell interaction on material surfaces, the expression of the leukocyte-endothelial CAMs: ICAM-1, VCAM-1, PECAM-1, and E-selectin on HUVECs were evaluated after U937 cell adhesion. The results demonstrated that plasma treated PET (T-PET) and treated PTFE (T-PTFE) did not increase U937 cell adhesion compared to the negative control. Maximal adhesion of U937 cells to HUVEC was observed on TNF-alpha stimulated endothelium with significant differences between day 1 and day 7, which is consistent with our prior observation that T-PET and T-PTFE did not cause HUVECs to increase the expression of adhesion molecules. After U937 cell adhesion, the expression of ICAM-1 and VCAM-1 of HUVECs were not different on T-PET and T-PTFE compared with the negative control. However, the expression of E-selectin was reduced on day 1, but not on day 7. The effects of plasma treated PET and PTFE on HUVEC adhesion and proliferation were also studied. On day 1 there were slight increases in the growth of HUVECs on both of T-PET and T-PTFE but this was not statistically significant. On day 7, the cell number increased significantly on the surfaces compared to the negative control. The results demonstrate that the plasma treatment of PET and PTFE with ammonia improves the adhesion and growth of endothelial cells and these surfaces do not exhibit a direct inflammatory effect in terms of monocyte adhesion and expression of

  14. Corneal Cell Adhesion to Contact Lens Hydrogel Materials Enhanced via Tear Film Protein Deposition

    PubMed Central

    Elkins, Claire M.; Qi, Qin M.; Fuller, Gerald G.

    2014-01-01

    Tear film protein deposition on contact lens hydrogels has been well characterized from the perspective of bacterial adhesion and viability. However, the effect of protein deposition on lens interactions with the corneal epithelium remains largely unexplored. The current study employs a live cell rheometer to quantify human corneal epithelial cell adhesion to soft contact lenses fouled with the tear film protein lysozyme. PureVision balafilcon A and AirOptix lotrafilcon B lenses were soaked for five days in either phosphate buffered saline (PBS), borate buffered saline (BBS), or Sensitive Eyes Plus Saline Solution (Sensitive Eyes), either pure or in the presence of lysozyme. Treated contact lenses were then contacted to a live monolayer of corneal epithelial cells for two hours, after which the contact lens was sheared laterally. The apparent cell monolayer relaxation modulus was then used to quantify the extent of cell adhesion to the contact lens surface. For both lens types, lysozyme increased corneal cell adhesion to the contact lens, with the apparent cell monolayer relaxation modulus increasing up to an order of magnitude in the presence of protein. The magnitude of this increase depended on the identity of the soaking solution: lenses soaked in borate-buffered solutions (BBS, Sensitive Eyes) exhibited a much greater increase in cell attachment upon protein addition than those soaked in PBS. Significantly, all measurements were conducted while subjecting the cells to moderate surface pressures and shear rates, similar to those experienced by corneal cells in vivo. PMID:25144576

  15. Corneal cell adhesion to contact lens hydrogel materials enhanced via tear film protein deposition.

    PubMed

    Elkins, Claire M; Qi, Qin M; Fuller, Gerald G

    2014-01-01

    Tear film protein deposition on contact lens hydrogels has been well characterized from the perspective of bacterial adhesion and viability. However, the effect of protein deposition on lens interactions with the corneal epithelium remains largely unexplored. The current study employs a live cell rheometer to quantify human corneal epithelial cell adhesion to soft contact lenses fouled with the tear film protein lysozyme. PureVision balafilcon A and AirOptix lotrafilcon B lenses were soaked for five days in either phosphate buffered saline (PBS), borate buffered saline (BBS), or Sensitive Eyes Plus Saline Solution (Sensitive Eyes), either pure or in the presence of lysozyme. Treated contact lenses were then contacted to a live monolayer of corneal epithelial cells for two hours, after which the contact lens was sheared laterally. The apparent cell monolayer relaxation modulus was then used to quantify the extent of cell adhesion to the contact lens surface. For both lens types, lysozyme increased corneal cell adhesion to the contact lens, with the apparent cell monolayer relaxation modulus increasing up to an order of magnitude in the presence of protein. The magnitude of this increase depended on the identity of the soaking solution: lenses soaked in borate-buffered solutions (BBS, Sensitive Eyes) exhibited a much greater increase in cell attachment upon protein addition than those soaked in PBS. Significantly, all measurements were conducted while subjecting the cells to moderate surface pressures and shear rates, similar to those experienced by corneal cells in vivo.

  16. Effect of mycophenolic acid on TNFα-induced expression of cell adhesion molecules in human venous endothelial cells in vitro

    PubMed Central

    Hauser, Ingeborg A; Johnson, David R; Thévenod, Frank; Goppelt-Strübe, Margarete

    1997-01-01

    Mycophenolic acid (MPA) is an inhibitor of inosine-5′-monophosphate dehydrogenase and therefore interferes with cellular GTP biosynthesis. Recently, MPA has been used as an antiproliferative and immunosuppressive agent. In the present study, the effect of MPA on the expression of the endothelial cell adhesion molecules (CAMs), intercellular (I) CAM-1, vascular (V) CAM-1 and endothelial (E)-selectin, was investigated in tumour necrosis factor-α (TNFα)-activated cultured human venous endothelial cells (EC).Surface expression of CAMs was measured by flow cytometry and mRNA expression by Northern blot analysis. Transcriptional activation of CAMs by the nuclear factor NF-κB was determined by an electromobility shift assay. The function of CAMs was studied by a static adhesion assay with human monocyte-like undifferentiated U937 cells.Pretreatment of TNFα- (5  ng ml−1, 12 h) activated EC with MPA (10 μM, 24 h) increased the binding of U937 cells, which had not been treated with MPA, by ≈amp;2 fold. MPA-pretreatment of EC did not affect TNFα-induced surface expression of ICAM-1. However, VCAM-1 and E-selectin were increased 2–3 fold and remained elevated up to 24 h, by which time TNFα-activated control EC had returned to baseline levels of expression. The effect of MPA on the surface expression of CAMs was half-maximal at ≈amp;1 μM and required ⩾12 h of pretreatment. Guanosine (0.3 mM), a precursor of GTP, did not prevent the effect of MPA on the expression of CAMs in TNFα-activated EC.Kinetics of mRNA expression of CAMs mirrored protein expression: mRNA for ICAM-1 was unaffected, whereas TNFα-induced mRNA expression for E-selectin and VCAM-1 was prolonged and increased by MPA. This effect was not due to increased transcription mediated by the nuclear transcription factor NF-κB. However, half-life for E-selectin mRNA was increased 10 fold by MPA, whereas ICAM-1 mRNA half-life was unchanged.The data demonstrate that apart from its

  17. Scaffold-forming and Adhesive Contributions of Synthetic Laminin-binding Proteins to Basement Membrane Assembly.

    PubMed

    McKee, Karen K; Capizzi, Stephanie; Yurchenco, Peter D

    2009-03-27

    Laminins that possess three short arms contribute to basement membrane assembly by anchoring to cell surfaces, polymerizing, and binding to nidogen and collagen IV. Although laminins containing the alpha4 and alpha5 subunits are expressed in alpha2-deficient congenital muscular dystrophy, they may be ineffective substitutes because they bind weakly to cell surfaces and/or because they lack the third arm needed for polymerization. We asked whether linker proteins engineered to bind to deficient laminins that provide such missing activities would promote basement membrane assembly in a Schwann cell model. A chimeric fusion protein (alphaLNNd) that adds a short arm terminus to laminin through the nidogen binding locus was generated and compared with the dystrophy-ameliorating protein miniagrin (mAgrin) that binds to the laminin coiled-coil dystroglycan and sulfatides. alphaLNNd was found to mediate laminin binding to collagen IV, to bind to galactosyl sulfatide, and to selectively convert alpha-short arm deletion-mutant laminins LmDeltaalphaLN and LmDeltaalphaLN-L4b into polymerizing laminins. This protein enabled polymerization-deficient laminin but not an adhesion-deficient laminin lacking LG domains (LmDeltaLG) to assemble an extracellular matrix on Schwann cell surfaces. mAgrin, on the other hand, enabled LmDeltaLG to form an extracellular matrix on cell surfaces without increasing accumulation of non-polymerizing laminins. These gain-of-function studies reveal distinct polymerization and anchorage contributions to basement membrane assembly in which the three different LN domains mediate the former, and the LG domains provide primary anchorage with secondary contributions from the alphaLN domain. These findings may be relevant for an understanding of the pathogenesis and treatment of laminin deficiency states.

  18. Folate deficiency and aberrant expression of cell adhesion molecule 1 are potential indicators of prognosis in laryngeal squamous cell carcinoma

    PubMed Central

    Chang, Hao; Ma, Min; Ma, Rui; Zhang, Chao; Zeng, Wei; Xing, Lu Qi

    2016-01-01

    The etiology of laryngeal squamous cell carcinoma (LSCC) has not yet been adequately examined. Therefore, the present study aimed to investigate the association between serum folate deficiency and abnormal expression of the cell adhesion molecule 1 (CADM1) protein in the progression of LSCC. Samples were collected from 60 patients with LSCC and 30 healthy people. Radioimmunoassays and immunohistochemical staining were performed to measure serum folate levels and CADM1 protein expression, respectively. The results demonstrated that CADM1 expression in LSCC specimens was significantly lower than in adjacent normal tissues (χ2=28.229, P<0.001), which was associated with histological differentiation and clinical stage (P=0.010 and 0.020, respectively). Levels of serum folate in patients with LSCC were significantly lower than those observed in healthy individuals (P=0.002). Furthermore, TSLCl expression and serum folate levels were positively correlated in LSCC (r=0.642, P=0.001). Thus, the present study determined that decreased CADM1 protein expression and low levels of serum folate were correlated with an increased severity of LSCC. PMID:28105160

  19. Effects of benidipine, a dihydropyridine-Ca2+ channel blocker, on expression of cytokine-induced adhesion molecules and chemoattractants in human aortic endothelial cells.

    PubMed

    Matsubara, Masahiro; Hasegawa, Kazuhide

    2004-09-13

    Benidipine hydrochloride (benidipine) is a dihydropyridine-Ca2+ channel blocker with antioxidant properties. We examined the effects of benidipine on cytokine-induced expression of adhesion molecules and chemokines, which play important roles in the adhesion of monocytes to endothelium. Pretreatment of human aortic endothelial cells (HAECs) with benidipine (0.3-10 micromol/l) for 24 h significantly suppressed cytokine-induced vascular cell adhesion molecule-1 (VCAM-1) and intracellular cell adhesion molecule-1 (ICAM-1) mRNA and protein expression, resulting in reduced adhesion of THP-1 monocytes. Benidipine also suppressed induction of monocyte chemoattractant protein (MCP)-1 and interleukin-8. Benidipine inhibited redox-sensitive transcriptional nuclear factor-kappaB (NF-kappaB) pathway, as determined by Western blotting of inhibitory kappaB (IkappaB) phosphorylation and luciferase reporter assay. Results of analysis using optical isomers of benidipine and antioxidants suggested that these inhibitory effects were dependent on pharmacological effects other than Ca2+ antagonism such as antioxidant effects. Benidipine may thus have anti-inflammatory properties and benefits for in the treatment of atherosclerosis.

  20. Discovery of a novel and conserved Plasmodium falciparum exported protein that is important for adhesion of PfEMP1 at the surface of infected erythrocytes

    PubMed Central

    Nacer, Adéla; Claes, Aurélie; Roberts, Amy; Scheidig-Benatar, Christine; Sakamoto, Hiroshi; Ghorbal, Mehdi; Lopez-Rubio, Jose-Juan; Mattei, Denise

    2015-01-01

    Plasmodium falciparum virulence is linked to its ability to sequester in post-capillary venules in the human host. Plasmodium falciparum erythrocyte membrane protein 1 (PfEMP1) is the main variant surface antigen implicated in this process. Complete loss of parasite adhesion is linked to a large subtelomeric deletion on chromosome 9 in a number of laboratory strains such as D10 and T9-96. Similar to the cytoadherent reference line FCR3, D10 strain expresses PfEMP1 on the surface of parasitized erythrocytes, however without any detectable cytoadhesion. To investigate which of the deleted subtelomeric genes may be implicated in parasite adhesion, we selected 12 genes for D10 complementation studies that are predicted to code for proteins exported to the red blood cell. We identified a novel single copy gene (PF3D7_0936500) restricted to P. falciparum that restores adhesion to CD36, termed here virulence-associated protein 1 (Pfvap1). Protein knockdown and gene knockout experiments confirmed a role of PfVAP1 in the adhesion process in FCR3 parasites. PfVAP1 is co-exported with PfEMP1 into the host cell via vesicle-like structures called Maurer's clefts. This study identifies a novel highly conserved parasite molecule that contributes to parasite virulence possibly by assisting PfEMP1 to establish functional adhesion at the host cell surface. PMID:25703704

  1. The role of serum proteins in Staphylococcus aureus adhesion to ethylene glycol coated surfaces.

    PubMed

    Schuster, Swen; Yu, Wenqi; Nega, Mulugeta; Chu, Ya-Yun; Zorn, Stefan; Zhang, Fajun; Götz, Friedrich; Schreiber, Frank

    2014-11-01

    Bacterial adhesion on implants is a first step in the development of chronic foreign body associated infections. Finding strategies to minimize bacterial adhesion may contribute to minimize such infections. It is known that surfaces with oligo-ethylene-glycol (EG3OMe) or poly-ethylene-glycol (PEG2k) terminations decrease unspecific protein adsorption and bacterial adhesion. However, little is known about the influence of serum and its components on bacterial adhesion. We therefore prepared two coatings on gold surface with HS-(CH2)11EG3OMe (EG3OMe) and PEG2k-thiol and studied the role of bovine serum albumin (BSA), γ-globulins, and serum on Staphylococcus aureus adhesion. While BSA and lysozyme showed no adherence even when applied at very high concentrations (100 mg/ml), γ-globulins adsorbed already from 10 mg/ml on. The adsorption of γ-globulins was, however, significantly decreased when it was mixed with BSA in a ratio of 3:1, as it is in the serum. Pretreatment of EG3OMe and PEG2k coatings with γ-globulins or serum strongly promoted adherence of S. aureus when resuspended in buffer, suggesting that γ-globulins play a pivotal role in promoting S. aureus adhesion by its IgG binding proteins; the finding that a spa-deletion mutant, lacking the IgG binding protein A, showed decreased adherence corroborated this. Similarly, when S. aureus was pretreated with serum or γ-globulins its adherence was also significantly decreased. Our findings show that particularly γ-globulins bind to the coated surfaces thus mediating adherence of S. aureus via its protein A. As pretreatment of S. aureus with serum or γ-globulins significantly decreased adherence, treatment of patients with γ-globulins before implant surgery might lower the risk of implant-associated infections.

  2. The Effect of Glass Ionomer and Adhesive Cements on Substance P Expression in Human Dental Pulp

    PubMed Central

    Ariza-Garcia, German; Camelo, Patricia; Mejia, Monica; Ojeda, Karyn; Azuero-Holguin, Maria M.; Abad-Coronel, Dunia; Munoz, Hugo R.

    2013-01-01

    Objectives: The purpose of this study was to quantify the effect of glass ionomer and adhesive cements on SP expression in healthy human dental pulp. Study Design: Forty pulp samples were obtained from healthy premolars where extraction was indicated for orthodontic reasons. In thirty of these premolars a Class V cavity preparation was performed and teeth were equally divided in three groups: Experimental Group I: Glass Ionomer cement was placed in the cavity. Experimental Group II: Adhesive Cement was placed in the cavity. Positive control group: Class V cavities only. The remaining ten healthy premolars where extracted without treatment and served as a negative control group. All pulp samples were processed and SP was measured by radioimmunoassay. Results: Greater SP expression was found in the adhesive cement group, followed by the glass ionomer and the positive control groups. The lower SP values were for the negative control group. ANOVA showed statistically significant differences between groups (p<0.0001). Tukey HSD post hoc tests showed statistically significant differences in SP expression between negative control group and the 3 other groups (p<0.01). Differences between the cavity-only group and the two experimental groups were also statistically significant (p<0.05 and p<0.01 respectively). There is also a statistically significant difference between the two experimental groups (p<0.01). Conclusions: These findings suggest that adhesive cements provoke a greater SP expression when compared with glass ionomer. Key words:Glass Ionomer, adhesive cement, Substance P, human dental pulp. PMID:23722145

  3. Loss of flotillin expression results in weakened desmosomal adhesion and Pemphigus vulgaris-like localisation of desmoglein-3 in human keratinocytes

    PubMed Central

    Völlner, Frauke; Ali, Jawahir; Kurrle, Nina; Exner, Yvonne; Eming, Rüdiger; Hertl, Michael; Banning, Antje; Tikkanen, Ritva

    2016-01-01

    Desmosomes are adhesion plaques that mediate cell-cell adhesion in many tissues, including the epidermis, and generate mechanical resistance to tissues. The extracellular domains of desmosomal cadherin proteins, desmogleins and desmocollins, are required for the interaction with cadherins of the neighbouring cells, whereas their cytoplasmic tails associate with cytoplasmic proteins which mediate connection to intermediate filaments. Disruption of desmosomal adhesion by mutations, autoantibodies or bacterial toxins results in severe human disorders of e.g. the skin and the heart. Despite the vital role of desmosomes in various tissues, the details of their molecular assembly are not clear. We here show that the two members of the flotillin protein family directly interact with the cytoplasmic tails of desmogleins. Depletion of flotillins in human keratinocytes results in weakened desmosomal adhesion and reduced expression of desmoglein-3, most likely due to a reduction in the desmosomal pool due to increased turnover. In the absence of flotillins, desmoglein-3 shows an altered localisation pattern in the cell-cell junctions of keratinocytes, which is highly similar to the localisation observed upon treatment with pemphigus vulgaris autoantibodies. Thus, our data show that flotillins, which have previously been connected to the classical cadherins, are also of importance for the desmosomal cell adhesion. PMID:27346727

  4. Loss of flotillin expression results in weakened desmosomal adhesion and Pemphigus vulgaris-like localisation of desmoglein-3 in human keratinocytes.

    PubMed

    Völlner, Frauke; Ali, Jawahir; Kurrle, Nina; Exner, Yvonne; Eming, Rüdiger; Hertl, Michael; Banning, Antje; Tikkanen, Ritva

    2016-06-27

    Desmosomes are adhesion plaques that mediate cell-cell adhesion in many tissues, including the epidermis, and generate mechanical resistance to tissues. The extracellular domains of desmosomal cadherin proteins, desmogleins and desmocollins, are required for the interaction with cadherins of the neighbouring cells, whereas their cytoplasmic tails associate with cytoplasmic proteins which mediate connection to intermediate filaments. Disruption of desmosomal adhesion by mutations, autoantibodies or bacterial toxins results in severe human disorders of e.g. the skin and the heart. Despite the vital role of desmosomes in various tissues, the details of their molecular assembly are not clear. We here show that the two members of the flotillin protein family directly interact with the cytoplasmic tails of desmogleins. Depletion of flotillins in human keratinocytes results in weakened desmosomal adhesion and reduced expression of desmoglein-3, most likely due to a reduction in the desmosomal pool due to increased turnover. In the absence of flotillins, desmoglein-3 shows an altered localisation pattern in the cell-cell junctions of keratinocytes, which is highly similar to the localisation observed upon treatment with pemphigus vulgaris autoantibodies. Thus, our data show that flotillins, which have previously been connected to the classical cadherins, are also of importance for the desmosomal cell adhesion.

  5. Diversity of bone matrix adhesion proteins modulates osteoblast attachment and organization of actin cytoskeleton.

    PubMed

    Demais, V; Audrain, C; Mabilleau, G; Chappard, D; Baslé, M F

    2014-06-01

    Interaction of cells with extracellular matrix is an essential event for differentiation, proliferation and activity of osteoblasts. In bone, binding of osteoblasts to bone matrix is required to determine specific activities of the cells and to synthesize matrix bone proteins. Integrins are the major cell receptors involved in the cell linkage to matrix proteins such as fibronectin, type I collagen and vitronectin, via the RGD-sequences. In this study, cultures of osteoblast-like cells (Saos-2) were done on coated glass coverslips in various culture conditions: DMEM alone or DMEM supplemented with poly-L-lysine (PL), fetal calf serum (FCS), fibronectin (FN), vitronectin (VN) and type I collagen (Col-I). The aim of the study was to determine the specific effect of these bone matrix proteins on cell adherence and morphology and on the cytoskeleton status. Morphological characteristics of cultured cells were studied using scanning electron microscopy and image analysis. The heterogeneity of cytoskeleton was studied using fractal analysis (skyscrapers and blanket algorithms) after specific preparation of cells to expose the cytoskeleton. FAK and MAPK signaling pathways were studied by western blotting in these various culture conditions. Results demonstrated that cell adhesion was reduced with PL and VN after 240 min. After 60 min of adhesion, cytoskeleton organization was enhanced with FN, VN and Col-I. No difference in FAK phosphorylation was observed but MAPK phosphorylation was modulated by specific adhesion on extracellular proteins. These results indicate that culture conditions modulate cell adhesion, cytoskeleton organization and intracellular protein pathways according to extracellular proteins present for adhesion.

  6. Effect of Milk Proteins on Adhesion of Bacteria to Stainless Steel Surfaces

    PubMed Central

    Barnes, L.-M.; Lo, M. F.; Adams, M. R.; Chamberlain, A. H. L.

    1999-01-01

    Stainless steel coupons were treated with skim milk and subsequently challenged with individual bacterial suspensions of Staphylococcus aureus, Pseudomonas fragi, Escherichia coli, Listeria monocytogenes, and Serratia marcescens. The numbers of attached bacteria were determined by direct epifluorescence microscopy and compared with the attachment levels on clean stainless steel with two different surface finishes. Skim milk was found to reduce adhesion of S. aureus, L. monocytogenes, and S. marcescens. P. fragi and E. coli attached in very small numbers to the clear surfaces, making the effect of any adsorbed protein layer difficult to assess. Individual milk proteins α-casein, β-casein, κ-casein, and α-lactalbumin were also found to reduce the adhesion of S. aureus and L. monocytogenes. The adhesion of bacteria to samples treated with milk dilutions up to 0.001% was investigated. X-ray photoelectron spectroscopy was used to determine the proportion of nitrogen in the adsorbed films. Attached bacterial numbers were inversely related to the relative atomic percentage of nitrogen on the surface. A comparison of two types of stainless steel surface, a 2B and a no. 8 mirror finish, indicated that the difference in these levels of surface roughness did not greatly affect bacterial attachment, and reduction in adhesion to a milk-treated surface was still observed. Cross-linking of adsorbed proteins partially reversed the inhibition of bacterial attachment, indicating that protein chain mobility and steric exclusion may be important in this phenomenon. PMID:10508087

  7. Low-Cost Soybean Protein Products as Extenders in Plywood Adhesives

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Soybean flour and meal were evaluated as alternate protein extenders in plywood adhesives. This research is part of our laboratory’s efforts to develop new uses for the proteinaceous co-products from soybean and cereal processing. Ground soybean meal was tested as replacement for wheat flour in gl...

  8. Low-cost Soybean Protein Products as Extenders in Plywood Adhesives

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Soybean flour and meal were evaluated as alternate protein extenders in plywood adhesives. This research is part of our laboratory’s efforts to develop new uses for the proteinaceous co-products from soybean and cereal processing. Ground soybean meal was tested as replacement for wheat flour in glu...

  9. Comparison of the adhesive performances of soy meal, water washed meal fractions, and protein isolates

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Adhesive bonding of wood plays an increasing role in the forest products industry and is a key factor for efficiently utilizing timber and other lignocellulosic resources. In this work, we obtained five soy meal products through commercial sources or in-house preparations. The protein content was 49...

  10. Conserved roles of the prion protein domains on subcellular localization and cell-cell adhesion.

    PubMed

    Solis, Gonzalo P; Radon, Yvonne; Sempou, Emily; Jechow, Katharina; Stuermer, Claudia A O; Málaga-Trillo, Edward

    2013-01-01

    Analyses of cultured cells and transgenic mice expressing prion protein (PrP) deletion mutants have revealed that some properties of PrP -such as its ability to misfold, aggregate and trigger neurotoxicity- are controlled by discrete molecular determinants within its protein domains. Although the contributions of these determinants to PrP biosynthesis and turnover are relatively well characterized, it is still unclear how they modulate cellular functions of PrP. To address this question, we used two defined activities of PrP as functional readouts: 1) the recruitment of PrP to cell-cell contacts in Drosophila S2 and human MCF-7 epithelial cells, and 2) the induction of PrP embryonic loss- and gain-of-function phenotypes in zebrafish. Our results show that homologous mutations in mouse and zebrafish PrPs similarly affect their subcellular localization patterns as well as their in vitro and in vivo activities. Among PrP's essential features, the N-terminal leader peptide was sufficient to drive targeting of our constructs to cell contact sites, whereas lack of GPI-anchoring and N-glycosylation rendered them inactive by blocking their cell surface expression. Importantly, our data suggest that the ability of PrP to homophilically trans-interact and elicit intracellular signaling is primarily encoded in its globular domain, and modulated by its repetitive domain. Thus, while the latter induces the local accumulation of PrPs at discrete punctae along cell contacts, the former counteracts this effect by promoting the continuous distribution of PrP. In early zebrafish embryos, deletion of either domain significantly impaired PrP's ability to modulate E-cadherin cell adhesion. Altogether, these experiments relate structural features of PrP to its subcellular distribution and in vivo activity. Furthermore, they show that despite their large evolutionary history, the roles of PrP domains and posttranslational modifications are conserved between mouse and zebrafish.

  11. The Ras suppressor Rsu-1 binds to the LIM 5 domain of the adaptor protein PINCH1 and participates in adhesion-related functions

    SciTech Connect

    Dougherty, Gerard W.; Chopp, Treasa; Qi Shengmei; Cutler, Mary Lou . E-mail: mcutler@usuhs.mil

    2005-05-15

    Rsu-1 is a highly conserved leucine rich repeat (LRR) protein that is expressed ubiquitously in mammalian cells. Rsu-1 was identified based on its ability to inhibit transformation by Ras, and previous studies demonstrated that ectopic expression of Rsu-1 inhibited anchorage-independent growth of Ras-transformed cells and human tumor cell lines. Using GAL4-based yeast two-hybrid screening, the LIM domain protein, PINCH1, was identified as the binding partner of Rsu-1. PINCH1 is an adaptor protein that localizes to focal adhesions and it has been implicated in the regulation of adhesion functions. Subdomain mapping in yeast revealed that Rsu-1 binds to the LIM 5 domain of PINCH1, a region not previously identified as a specific binding domain for any other protein. Additional testing demonstrated that PINCH2, which is highly homologous to PINCH1, except in the LIM 5 domain, does not interact with Rsu-1. Glutathione transferase fusion protein binding studies determined that the LRR region of Rsu-1 interacts with PINCH1. Transient expression studies using epitope-tagged Rsu-1 and PINCH1 revealed that Rsu-1 co-immunoprecipitated with PINCH1 and colocalized with vinculin at sites of focal adhesions in mammalian cells. In addition, endogenous P33 Rsu-1 from 293T cells co-immunoprecipitated with transiently expressed myc-tagged PINCH1. Furthermore, RNAi-induced reduction in Rsu-1 RNA and protein inhibited cell attachment, and while previous studies demonstrated that ectopic expression of Rsu-1 inhibited Jun kinase activation, the depletion of Rsu-1 resulted in activation of Jun and p38 stress kinases. These studies demonstrate that Rsu-1 interacts with PINCH1 in mammalian cells and functions, in part, by altering cell adhesion.

  12. Endometrial Expression of Homeobox Genes and Cell Adhesion Molecules in Infertile Women With Intramural Fibroids During Window of Implantation.

    PubMed

    Makker, Annu; Goel, Madhu Mati; Nigam, Dipti; Bhatia, Vikram; Mahdi, Abbas Ali; Das, Vinita; Pandey, Amita

    2017-03-01

    This study was designed to examine the expression and cellular distribution of homeobox ( HOX) genes ( HOXA10 and HOXA11) and cell adhesion molecules (E-cadherin, N-cadherin, and β-catenin) during the window of implantation in infertile women with noncavity-distorting intramural (IM) fibroids (n = 18) and in fertile controls (n = 12). Quantitative real-time polymerase chain reaction and immunohistochemistry were used to evaluate the messenger RNA (mRNA) levels and protein expression, respectively. When compared to fertile controls, reduced HOXA10 and HOXA11 transcript and protein levels were observed in infertile women. However, changes only in the expression of HOXA10 mRNA (-1.72-fold; P = .03) and stromal protein ( P = .001) were statistically significant. Significantly lower E-cadherin mRNA (-10.97-fold; P = .02) and protein levels were seen in infertile patients. E-cadherin immunostaining was significantly reduced both in the luminal ( P = .048) and in the glandular ( P = .014) epithelium of endometrium from infertile patients when compared to controls. No significant change was observed either in the mRNA levels or in the immunoexpression of N-cadherin and β-catenin. However, a trend toward lower N-cadherin expression in the luminal epithelium ( P = .054) and decreased β-catenin expression in the glandular epithelium ( P = .070) was observed in infertile patients. The present findings suggest that altered endometrial HOXA10 and E-cadherin mRNA and protein expression observed in infertile women with IM fibroids during the mid-secretory phase might impair endometrial receptivity leading to infertility in these patients.

  13. Effects of nitrogen dioxide on the expression of intercellular adhesion molecule-1, neutrophil adhesion, and cytotoxicity: studies in human bronchial epithelial cells.

    PubMed

    Ayyagari, Vijayalakshmi N; Januszkiewicz, Adolph; Nath, Jayasree

    2007-02-01

    Nitrogen Dioxide (NO2) is a product of high-temperature combustion and an environmental oxidant of concern. We have recently reported that early changes in NO2-exposed human bronchial epithelial cells are causally linked to increased generation of proinflammatory mediators, such as nitric oxide/nitrite and cytokines like interleukin (IL)-1beta, tumor necrosis factor (TNF)-alpha and IL-8. The objective of the present in vitro study was to further delineate the cellular mechanisms of NO2-mediated toxicity, and to define the nature of cell death that ensues upon exposure of normal human bronchial epithelial (NHBE) cells to a brief high dose of NO2. Our results demonstrate that the NHBE cells undergo apoptotic cell death during the early post-NO2 period, but this is independent of any significant increase in caspase-3 activity. However, necrotic cell death was more prevalent at later time intervals. Interestingly, an increased expression of HO-1, a redox-sensitive stress protein, was observed in NO2-exposed NHBE cells at 24 h. Since neutrophils (PMNs) play an active role in acute lung inflammation and resultant oxidative injury, we also investigated changes in human PMN-NHBE cell interactions. As compared to normal cells, increased adhesion of PMNs to NO2-exposed cells was observed, which resulted in an increased NHBE cell death. The latter was also increased in the presence of IL-8 and TNF-alpha + interferon (IFN)-gamma, which correlated with upregulation of intercellular adhesion molecule-1 (ICAM-1). Our results confirmed an involvement of nitric oxide (NO) in NO2-induced cytotoxicity. By using NO synthase inhibitors such as L-NAME and 3-aminoguanidine (AG), a significant decrease in cell death, PMN adhesion, and ICAM-1 expression was observed. These findings indicate a role for the L-arginine/NO synthase pathway in the observed NO2-mediated toxicity in NHBE cells. Therapeutic strategies aimed at controlling excess generation of NO and/or inflammatory cytokines may

  14. Activated peripheral lymphocytes with increased expression of cell adhesion molecules and cytotoxic markers are associated with dengue fever disease.

    PubMed

    Azeredo, Elzinandes L; Zagne, Sonia M O; Alvarenga, Allan R; Nogueira, Rita M R; Kubelka, Claire F; de Oliveira-Pinto, Luzia M

    2006-06-01

    The immune mechanisms involved in dengue fever and dengue hemorrhagic/dengue shock syndrome are not well understood. The ex vivo activation status of immune cells during the dengue disease in patients was examined. CD4 and CD8 T cells were reduced during the acute phase. Interestingly, CD8 T cells co-expressing activation marker HLA-DR, Q, P, and cytolytic granule protein-Tia-1 were significantly higher in dengue patients than in controls. Detection of adhesion molecules indicated that in dengue patients the majority of T cells (CD4 and CD8) express the activation/memory phenotype, characterized as CD44HIGH and lack the expression of the naïve cell marker, CD62L LOW. Also, the levels of T cells co-expressing ICAM-1 (CD54), VLA-4, and LFA-1 (CD11a) were significantly increased. CD8 T lymphocytes expressed predominantly low levels of anti-apoptotic molecule Bcl-2 in the acute phase, possibly leading to the exhibition of a phenotype of activated/effector cells. Circulating levels of IL-18, TGF-b1 and sICAM-1 were significantly elevated in dengue patients. Early activation events occur during acute dengue infection which might contribute to viral clearance. Differences in expression of adhesion molecules among CD4 and CD8 T cells might underlie the selective extravasation of these subsets from blood circulation into lymphoid organs and/or tissues. In addition, activated CD8 T cells would be more susceptible to apoptosis as shown by the alteration in Bcl-2 expression. Cytokines such as IL-18, TGF-b1, and sICAM-1 may be contributing by either stimulating or suppressing the adaptative immune response, during dengue infection, thereby perhaps establishing a relationship with disease severity.

  15. Congeneric bio-adhesive mussel foot proteins designed by modified prolines revealed a chiral bias in unnatural translation.

    PubMed

    Larregola, Maud; Moore, Shannon; Budisa, Nediljko

    2012-05-18

    Chiral bias in the unnatural translation and 'sticky' mussel proteins. The residue-specific in vivo incorporation of hydroxylated amino acids as well as other synthetic analogs, such as fluoroprolines, emerges as the method of choice for recombinant synthesis of Pro-rich mussel adhesive protein congeners. Chemical diversifications introduced in this way provide a general route towards bio-adhesive congeners endowed with properties not developed by natural evolution. Most importantly, we have found that the co-translational incorporation of (4R)-, and (4S)-hyroxylated and fluorinated analogs into mussel proteins presented a chiral bias: the expressed protein was only detectable in samples incubated with analogs with (4R)-substituents. Possible relationship of these stereochemical preferences for (4R)-stereoisomers in the translation to intracellular tRNA concentrations, ribosomal editing and proofreading or structural effects such as preorganization remains to be addressed in future studies. These studies will generally provide a mechanistic framework for the flexibility of the translational machinery and establish the boundaries of the unnatural translation.

  16. Human epididymis protein 4 (HE4) plays a key role in ovarian cancer cell adhesion and motility

    SciTech Connect

    Lu, Renquan; Sun, Xinghui; Xiao, Ran; Zhou, Lei; Gao, Xiang; Guo, Lin

    2012-03-09

    Highlights: Black-Right-Pointing-Pointer We generated stable transduced HE4 overexpression and knockdown cells. Black-Right-Pointing-Pointer HE4 was associated with EOC cell adhesion and motility. Black-Right-Pointing-Pointer HE4 might have some effects on activation of EGFR-MAPK signaling pathway. Black-Right-Pointing-Pointer HE4 play an important role in EOC tumorigenicity. -- Abstract: Human epididymis protein 4 (HE4) is a novel and specific biomarker for epithelial ovarian cancer (EOC). We previously demonstrated that serum HE4 levels were significantly elevated in the majority of EOC patients but not in subjects with benign disease or healthy controls. However, the precise mechanism of HE4 protein function is unknown. In this study, we generated HE4-overexpressing SKOV3 cells and found that stably transduced cells promoted cell adhesion and migration. Knockdown of HE4 expression was achieved by stable transfection of SKOV3 cells with a construct encoding a short hairpin DNA directed against the HE4 gene. Correspondingly, the proliferation and spreading ability of HE4-expressed cells were inhibited by HE4 suppression. Mechanistically, impaired EGFR and Erk1/2 phosphorylation were observed in cells with HE4 knockdown. The phosphorylation was restored when the knockdown cells were cultured in conditioned medium containing HE4. Moreover, in vivo tumorigenicity showed that HE4 suppression markedly inhibited the growth of tumors. This suggests that expression of HE4 is associated with cancer cell adhesion, migration and tumor growth, which can be related to its effects on the EGFR-MAPK signaling pathway. Our results provide evidence of the cellular and molecular mechanisms that may underlie the motility-promoting role of HE4 in EOC progression. The role of HE4 as a target for gene-based therapy might be considered in future studies.

  17. Expression of COX-2 in platelet-monocyte interactions occurs via combinatorial regulation involving adhesion and cytokine signaling

    PubMed Central

    Dixon, Dan A.; Tolley, Neal D.; Bemis-Standoli, Kristi; Martinez, Mark L.; Weyrich, Andrew S.; Morrow, Jason D.; Prescott, Stephen M.; Zimmerman, Guy A.

    2006-01-01

    Tight regulation of COX-2 expression is a key feature controlling eicosanoid production in atherosclerosis and other inflammatory syndromes. Adhesive interactions between platelets and monocytes occur in these conditions and deliver specific signals that trigger inflammatory gene expression. Using a cellular model of monocyte signaling induced by activated human platelets, we identified the central posttranscriptional mechanisms that regulate timing and magnitude of COX-2 expression. Tethering of monocytes to platelets and to purified P-selectin, a key adhesion molecule displayed by activated platelets, induces NF-κB activation and COX-2 promoter activity. Nevertheless, COX-2 mRNA is rapidly degraded, leading to aborted protein synthesis. Time-dependent signaling of monocytes induces a second phase of transcript accumulation accompanied by COX-2 enzyme synthesis and eicosanoid production. Here, generation of IL-1β, a proinflammatory cytokine, promoted stabilization of COX-2 mRNA by silencing of the AU-rich mRNA decay element (ARE) in the 3′-untranslated region (3'UTR) of the mRNA. Consistent with observed mRNA stabilization, activated platelets or IL-1β treatment induced cytoplasmic accumulation and enhanced ARE binding of the mRNA stability factor HuR in monocytes. These findings demonstrate that activated platelets induce COX-2 synthesis in monocytes by combinatorial signaling to transcriptional and posttranscriptional checkpoints. These checkpoints may be altered in disease and therefore useful as targets for antiinflammatory intervention. PMID:16998585

  18. Human DCXR - another 'moonlighting protein' involved in sugar metabolism, carbonyl detoxification, cell adhesion and male fertility?

    PubMed

    Ebert, Bettina; Kisiela, Michael; Maser, Edmund

    2015-02-01

    Dicarbonyl/L-xylulose reductase (DCXR; SDR20C1), a member of the short-chain dehydrogenase/reductase (SDR) superfamily catalyzes the reduction of α-dicarbonyl compounds and monosaccharides. Its role in the metabolism of L-xylulose has been known since 1970, when essential pentosuria was found to be associated with DCXR deficiency. Despite its early discovery, our knowledge about the role of human DCXR in normal physiology and pathophysiology is still incomplete. Sporadic studies have demonstrated aberrant expression in several cancers, but their physiological significance is unknown. In reproductive medicine, where DCXR is commonly referred to as 'sperm surface protein P34H', it serves as marker for epididymal sperm maturation and is essential for gamete interaction and successful fertilization. DCXR exhibits a multifunctional nature, both acting as a carbonyl reductase and also performing non-catalytic functions, possibly resulting from interactions with other proteins. Recent observations associate DCXR with a role in cell adhesion, pointing to a novel function involving tumour progression and possibly metastasis. This review summarizes the current knowledge about human DCXR and its orthologs from mouse and Caenorhabditis elegans (DHS-21) with an emphasis on its multifunctional characteristics. Due to its close structural relationship with DCXR, carbonyl reductase 2 (Cbr2), a tetrameric enzyme found in several non-primate species is also discussed. Similar to human DCXR, Cbr2 from golden hamster (P26h) and cow (P25b) is essential for sperm-zona pellucida interaction and fertilization. Because of the apparent similarity of these two proteins and the inconsistent use of alternative names previously, we provide an overview of the systematic classification of DCXR and Cbr2 and a phylogenetic analysis to illustrate their ancestry.

  19. Magnolol reduced TNF-α-induced vascular cell adhesion molecule-1 expression in endothelial cells via JNK/p38 and NF-κB signaling pathways.

    PubMed

    Liang, Chan-Jung; Lee, Chiang-Wen; Sung, Hsin-Ching; Chen, Yung-Hsiang; Wang, Shu-Huei; Wu, Pei-Jhen; Chiang, Yao-Chang; Tsai, Jaw-Shiun; Wu, Chau-Chung; Li, Chi-Yuan; Chen, Yuh-Lien

    2014-01-01

    Expression of cell adhesion molecules by the endothelium and the attachment of leukocytes to these cells play major roles in inflammation and cardiovascular disorders. Magnolol, a major active component of Magnolia officinalis, has antioxidative and anti-inflammatory properties. In the present study, the effects of magnolol on the expression of vascular cell adhesion molecule-1 (VCAM-1) in human aortic endothelial cells (HAECs) and the related mechanisms were investigated. TNF-α induced VCAM-1 protein expression and mRNA stability were significantly decreased in HAECs pre-treated with magnolol. Magnolol significantly reduced the phosphorylation of ERK, JNK, and p38 in TNF-α-treated HAECs. The decrease in VCAM-1 expression in response to TNF-α treatment was affected by JNK and p38 inhibitors, not by an ERK inhibitor. Magnolol also attenuates NF-κB activation and the translocation of HuR (an RNA binding protein) in TNF-α-stimulated HAECs. The VCAM-1 expression was weaker in the aortas of TNF-α-treated apo-E deficient mice with magnolol treatment. These data demonstrate that magnolol inhibits TNF-α-induced JNK/p38 phosphorylation, HuR translocation, NF-κB activation, and thereby suppresses VCAM-1 expression resulting in reduced leukocyte adhesion. Taken together, these results suggest that magnolol has an anti-inflammatory property and may play an important role in the prevention of atherosclerosis and inflammatory responses.

  20. A novel domain cassette identifies Plasmodium falciparum PfEMP1 proteins binding ICAM-1 and is a target of cross-reactive, adhesion-inhibitory antibodies.

    PubMed

    Bengtsson, Anja; Joergensen, Louise; Rask, Thomas S; Olsen, Rebecca W; Andersen, Marianne A; Turner, Louise; Theander, Thor G; Hviid, Lars; Higgins, Matthew K; Craig, Alister; Brown, Alan; Jensen, Anja T R

    2013-01-01

    Cerebral Plasmodium falciparum malaria is characterized by adhesion of infected erythrocytes (IEs) to the cerebral microvasculature. This has been linked to parasites expressing the structurally related group A subset of the P. falciparum erythrocyte membrane protein 1 (PfEMP1) family of IE adhesion ligands and to IEs with affinity for ICAM-1. However, recent evidence has cast doubt on both these associations, tempering hopes of the feasibility of developing a vaccine based on ICAM-1-binding PfEMP1. In this study, we report the identification of a domain cassette (DC) present in group A var genes from six genetically distinct P. falciparum parasites. The three domains in the cassette, which we call DC4, had a high level of sequence identity and cluster together phylogenetically. Erythrocytes infected by these parasites and selected in vitro for expression of DC4 adhered specifically to ICAM-1. The ICAM-1-binding capacity of DC4 was mapped to the C-terminal third of its Duffy-binding-like β3 domain. DC4 was the target of broadly cross-reactive and adhesion-inhibitory IgG Abs, and levels of DC4-specific and adhesion-inhibitory IgG increased with age among P. falciparum-exposed children. Our study challenges earlier conclusions that group A PfEMP1 proteins are not central to ICAM-1-specific IE adhesion and support the feasibility of developing a vaccine preventing cerebral malaria by inhibiting cerebral IE sequestration.

  1. Correlating the kinetics of cytokine-induced E-selectin adhesion and expression on endothelial cells.

    PubMed Central

    Levin, J D; Ting-Beall, H P; Hochmuth, R M

    2001-01-01

    Many human diseases are mediated through the immune system. In chronic inflammatory disorders, the processes ordinarily involved in tissue healing become destructive. Endothelial cells normally recruit leukocytes to inflamed tissue using cytokine-induced adhesion receptors on the surfaces of interacting cells. Leukocyte capture depends on specialized characteristics of these receptors, particularly the binding kinetics. This study is designed to clarify the relationship between cytokine-induced changes in cell properties and binding kinetics. Here, we measure the kinetics of expression and monoclonal antibody binding for E-selectin in interleukin-1alpha-stimulated microvascular endothelium in vitro and incorporate the data into kinetic models. Quantitative flow cytometry is used to determine molecular density (expression), and micropipette assays are used to find the probability of adhesion (function). Within five hours of interleukin-1alpha stimulation, E-selectin density increases from 0 to 742 sites/microm(2), and antibody-E-selectin adhesion probability increases from a baseline of 6.3% to 64%. A kinetic model is applied to find an apparent association rate constant, k(f), of 3.7 x 10(-14) cm(2)/sec for antibody-E-selectin binding. Although the model successfully predicts experimental results, the rate constant is undervalued for a diffusion-limited process, suggesting that functional adhesion may be modified through cytokine-induced changes in microtopology and receptor localization. PMID:11159434

  2. Exenatide Alters Gene Expression of Neural Cell Adhesion Molecule (NCAM), Intercellular Cell Adhesion Molecule (ICAM), and Vascular Cell Adhesion Molecule (VCAM) in the Hippocampus of Type 2 Diabetic Model Mice

    PubMed Central

    Gumuslu, Esen; Cine, Naci; Gökbayrak, Merve Ertan; Mutlu, Oguz; Celikyurt, Ipek Komsuoglu; Ulak, Guner

    2016-01-01

    Background Glucagon-like peptide-1 (GLP-1), a potent and selective agonist for the GLP-1 receptor, ameliorates the symptoms of diabetes through stimulation of insulin secretion. Exenatide is a potent and selective agonist for the GLP-1 receptor. Cell adhesion molecules are members of the immunoglobulin superfamily and are involved in synaptic rearrangements in the mature brain. Material/Methods The present study demonstrated the effects of exenatide treatment (0.1 μg/kg, subcutaneously, twice daily for 2 weeks) on the gene expression levels of cell adhesion molecules, neural cell adhesion molecule (NCAM), intercellular cell adhesion molecule (ICAM), and vascular cell adhesion molecule (VCAM) in the brain tissue of diabetic BALB/c male mice by real-time quantitative polymerase chain reaction (PCR). Diabetes was induced by streptozotocin/nicotinamide (STZ-NA) injection to male mice. Results The results of this study revealed that hippocampal gene expression of NCAM, ICAM, and VCAM were found to be up-regulated in STZ-NA-induced diabetic mice compared to those of controls. A significant decrease in the gene expression levels of NCAM, ICAM, and VCAM were determined after 2 weeks of exenatide administration. Conclusions Cell adhesion molecules may be involved in the molecular mechanism of diabetes. Exenatide has a strong beneficial action in managing diabetes induced by STZ/NA by altering gene expression of NCAM, ICAM, and VCAM. PMID:27465247

  3. Nuclear magnetic resonance spectroscopy of mussel adhesive protein repeating peptide segment.

    PubMed

    Olivieri, M P; Wollman, R M; Alderfer, J L

    1997-12-01

    Mussel adhesive protein (MAP) is the adhesive agent used by the common blue sea mussel (Mytilus edulis) to attach the animal to various underwater surfaces. It is generally composed of 75 to 85 repeating decameric units with the reported primary sequence NH2-Ala(1)-Lyst(2)-Pro(3)-Ser(4)-Tyr(5)-Hyp(6)-Hyp(7)-Thr(8)-DOPA( 9)- Lys(10)-COOH. This study examines this peptide's solution-state conformation using proton nuclear magnetic resonance (NMR) spectroscopy. NMR and molecular modeling of the decamer before and after molecular dynamics calculations in water suggests a conformation that retains an overall bent helix.

  4. The Anti-Atherosclerotic Effect of Naringin Is Associated with Reduced Expressions of Cell Adhesion Molecules and Chemokines through NF-κB Pathway.

    PubMed

    Hsueh, Tun-Pin; Sheen, Jer-Ming; Pang, Jong-Hwei S; Bi, Kuo-Wei; Huang, Chao-Chun; Wu, Hsiao-Ting; Huang, Sheng-Teng

    2016-02-05

    Naringin has been reported to have an anti-atherosclerosis effect but the underlying mechanism is not fully understood. The aim of this study is to investigate the impact of naringin on the TNF-α-induced expressions of cell adhesion molecules, chemokines and NF-κB signaling pathway in human umbilical vein endothelial cells (HUVECs). The experiments revealed that naringin, at concentrations without cytotoxicity, dose-dependently inhibited the adhesion of THP-1 monocytes to the TNF-α-stimulated HUVECs. The TNF-α-induced expressions of cell adhesion molecules, including VCAM-1, ICAM-1 and E-selectin, at both the mRNA and protein levels, were significantly suppressed by naringin in a dose dependent manner. In addition, the TNF-α-induced mRNA and protein levels of chemokines, including fractalkine/CX3CL1, MCP-1 and RANTES, were also reduced by naringin. Naringin significantly inhibited TNF-α-induced nuclear translocation of NF-κB, which resulted from the inhibited phosphorylation of IKKα/β, IκB-α and NF-κB. Altogether, we proposed that naringin modulated TNF-α-induced expressions of cell adhesion molecules and chemokines through the inhibition of TNF-α-induced activation of IKK/NF-κB signaling pathway to exert the anti-atherosclerotic effect.

  5. Experimental Cerebral Malaria Develops Independently of Endothelial Expression of Intercellular Adhesion Molecule-1 (ICAM-1)*

    PubMed Central

    Ramos, Theresa N.; Bullard, Daniel C.; Darley, Meghan M.; McDonald, Kristin; Crawford, David F.; Barnum, Scott R.

    2013-01-01

    Cerebral malaria (CM) is a severe clinical complication of Plasmodium falciparum malaria infection and is characterized by a high fatality rate and neurological damage. Sequestration of parasite-infected red blood cells in brain microvasculature utilizes host- and parasite-derived adhesion molecules and is an important factor in the development of CM. ICAM-1, an alternatively spliced adhesion molecule, is believed to be critical on endothelial cells for infected red blood cell sequestration in CM. Using ICAM-1 mutant mice, we found that the full-length ICAM-1 isoform is not required for development of murine experimental CM (ECM) and that ECM phenotype varies with the combination of ICAM-1 isoforms expressed. Furthermore, we observed development of ECM in transgenic mice expressing ICAM-1 only on leukocytes, indicating that endothelial cell expression of this adhesion molecule is not required for disease pathogenesis. We propose that ICAM-1-dependent cellular aggregation, independent of ICAM-1 expression on the cerebral microvasculature, contributes to ECM. PMID:23493396

  6. Experimental cerebral malaria develops independently of endothelial expression of intercellular adhesion molecule-1 (icam-1).

    PubMed

    Ramos, Theresa N; Bullard, Daniel C; Darley, Meghan M; McDonald, Kristin; Crawford, David F; Barnum, Scott R

    2013-04-19

    Cerebral malaria (CM) is a severe clinical complication of Plasmodium falciparum malaria infection and is characterized by a high fatality rate and neurological damage. Sequestration of parasite-infected red blood cells in brain microvasculature utilizes host- and parasite-derived adhesion molecules and is an important factor in the development of CM. ICAM-1, an alternatively spliced adhesion molecule, is believed to be critical on endothelial cells for infected red blood cell sequestration in CM. Using ICAM-1 mutant mice, we found that the full-length ICAM-1 isoform is not required for development of murine experimental CM (ECM) and that ECM phenotype varies with the combination of ICAM-1 isoforms expressed. Furthermore, we observed development of ECM in transgenic mice expressing ICAM-1 only on leukocytes, indicating that endothelial cell expression of this adhesion molecule is not required for disease pathogenesis. We propose that ICAM-1-dependent cellular aggregation, independent of ICAM-1 expression on the cerebral microvasculature, contributes to ECM.

  7. Adhesions of extracellular surface-layer associated proteins in Lactobacillus M5-L and Q8-L.

    PubMed

    Zhang, Yingchun; Xiang, Xinling; Lu, Qianhui; Zhang, Lanwei; Ma, Fang; Wang, Linlin

    2016-02-01

    Surface-layer associated proteins (SLAP) that envelop Lactobacillus paracasei ssp. paracasei M5-L and Lactobacillus casei Q8-L cell surfaces are involved in the adherence of these strain to the human intestinal cell line HT-29. To further elucidate some of the properties of these proteins, we assessed the yields and expressions of SLAP under different incubation conditions. An efficient and selective extraction of SLAP was obtained when cells of Lactobacillus were treated with 5 M LiCl at 37°C in aerobic conditions. The SLAP of Lactobacillus M5-L and Q8-L in cell extracts were visualized by SDS-PAGE and identified by Western blotting with sulfo-N-hydroxysuccinimide-biotin-labeled HT-29 cells as adhesion proteins. Atomic force microscopy contact imaging revealed that Lactobacillus strains M5-L and Q8-L normally display a smooth, homogeneous surface, whereas the surfaces of M5-L and Q8-L treated with 5 M LiCl were rough and more heterogeneous. Analysis of adhesion forces revealed that the initial adhesion forces of 1.41 and 1.28 nN obtained for normal Lactobacillus M5-L and Q8-L strains, respectively, decreased to 0.70 and 0.48 nN, respectively, following 5 M LiCl treatment. Finally, the dominant 45-kDa protein bands of Lactobacillus Q8-L and Lactobacillus M5-L were identified as elongation factor Tu and surface antigen, respectively, by liquid chromatography-tandem mass spectrometry.

  8. Human Immunodeficiency Virus (HIV) Type 1 Vpu Induces the Expression of CD40 in Endothelial Cells and Regulates HIV-Induced Adhesion of B-Lymphoma Cells

    PubMed Central

    Henderson, Winnie W.; Ruhl, Rebecca; Lewis, Paul; Bentley, Matthew; Nelson, Jay A.; Moses, Ashlee V.

    2004-01-01

    AIDS-related B-cell non-Hodgkin's lymphoma (AIDS-NHL) is a significant cause of morbidity and mortality among individuals infected with human immunodeficiency virus type 1 (HIV-1). AIDS-NHL is clinically and histologically heterogeneous, but common features include an aggressive clinical course and frequent extranodal presentation. HIV-1 infection of nonimmune cells that interact with malignant B cells at extranodal sites may influence both the development and the clinical presentation of disease. Our previous studies have shown that coculture of B-lymphoma (BL) cells with HIV-1-infected endothelial cells (EC) leads to contact activation of EC and firm BL-cell adhesion. The key event promoting EC-BL-cell adhesion was HIV-1 upregulation of endothelial CD40, which allowed induction of vascular cell adhesion molecule 1 (VCAM-1) in a CD40-dependent manner. The present study was designed to identify the HIV-1 protein(s) that influence EC-BL-cell adhesion. When HIV-1 proteins were individually expressed in EC by using recombinant adenoviruses, cultured BL cells adhered exclusively to Vpu-transduced EC. As with HIV-infected EC, adhesive properties were linked to the capacity of Vpu to upregulate CD40, which in turn allowed efficient expression of VCAM-1. When EC were infected with an HIV-1 pseudotype lacking the Vpu gene, CD40 upregulation and BL-cell adhesive properties were lost, indicating an essential role for Vpu in EC-BL-cell interactions. Thus, these data reveal a novel function for HIV-1 Vpu and further suggest a role for Vpu in the development of AIDS-NHL at EC-rich extranodal sites. PMID:15078922

  9. An Underwater Surface-Drying Peptide Inspired by a Mussel Adhesive Protein

    PubMed Central

    Wei, Wei; Petrone, Luigi; Tan, YerPeng; Cai, Hao; Israelachvili, Jacob N.; Miserez, Ali

    2016-01-01

    Water hampers the formation of strong and durable bonds between adhesive polymers and solid surfaces, in turn hindering the development of adhesives for biomedical and marine applications. Inspired by mussel adhesion, a mussel foot protein homologue (mfp3S-pep) is designed, whose primary sequence is designed to mimic the pI, polyampholyte, and hydrophobic characteristics of the native protein. Noticeably, native protein and synthetic peptide exhibit similar abilities to self-coacervate at given pH and ionic strength. 3,4-dihydroxy-l-phenylalanine (Dopa) proves necessary for irreversible peptide adsorption to both TiO2 (anatase) and hydroxyapatite (HAP) surfaces, as confirmed by quartz crystal microbalance measurements, with the coacervate showing superior adsorption. The adsorption of Dopa-containing peptides is investigated by attenuated total reflection infrared spectroscopy, revealing initially bidentate coordinative bonds on TiO2, followed by H-bonded and eventually long-ranged electrostatic and Van der Waals interactions. On HAP, mfp3s-pep-3Dopa adsorption occurs predominantly via H-bond and outer-sphere complexes of the catechol groups. Importantly, only the Dopa-bearing compounds are able to remove interfacial water from the target surfaces, with the coacervate achieving the highest water displacement arising from its superior wetting properties. These findings provide an impetus for developing coacervated Dopa-functionalized peptides/polymers adhesive formulations for a variety of applications on wet polar surfaces. PMID:27840600

  10. Rapidly light-activated surgical protein glue inspired by mussel adhesion and insect structural crosslinking.

    PubMed

    Jeon, Eun Young; Hwang, Byeong Hee; Yang, Yun Jung; Kim, Bum Jin; Choi, Bong-Hyuk; Jung, Gyu Yong; Cha, Hyung Joon

    2015-10-01

    Currently approved surgical tissue glues do not satisfy the requirements for ideal bioadhesives due to limited adhesion in wet conditions and severe cytotoxicity. Herein, we report a new light-activated, mussel protein-based bioadhesive (LAMBA) inspired by mussel adhesion and insect dityrosine crosslinking chemistry. LAMBA exhibited substantially stronger bulk wet tissue adhesion than commercially available fibrin glue and good biocompatibility in both in vitro and in vivo studies. Besides, the easily tunable, light-activated crosslinking enabled an effective on-demand wound closure and facilitated wound healing. Based on these outstanding properties, LAMBA holds great potential as an ideal surgical tissue glue for diverse medical applications, including sutureless wound closures of skin and internal organs.

  11. The impact of grafted modification of silicone surfaces with quantum-sized materials on protein adsorption and bacterial adhesion.

    PubMed

    Nune, C; Xu, W; Misra, R D K

    2012-12-01

    The majority of the infections associated with the biomedical devices including cardiovascular implants and catheters are instigated by the adhesion of bacteria including staphylococcus aureus, which is subsequently followed by biofilm formation. Keeping in mind the detrimental effect of bacterial adhesion, the objective of the study is to probe the impact of grafted modification of silicone surfaces with quantum-sized carbon on biofilm formation. Also, explored is the effect of protein adsorption on modified surface and its subsequent influence on bacterial adhesion. We compare and contrast the architecture and foot print of protein adsorption on unmodified and modified model silicone surfaces on bacterial adhesion. The study underscores that protein adsorption on quantum-sized carbon-grafted surface acts as a repellant for bacterial adhesion because of steric repulsion between the negatively charged protein and bacteria. Thus, we establish here the efficacy of modified surfaces in preventing biofilm formation.

  12. The oxidase activity of vascular adhesion protein-1 (VAP-1) is essential for function.

    PubMed

    Noonan, Thomas; Lukas, Susan; Peet, Gregory W; Pelletier, Josephine; Panzenbeck, Mark; Hanidu, Adedayo; Mazurek, Suzanne; Wasti, Ruby; Rybina, Irina; Roma, Teresa; Kronkaitis, Anthony; Shoultz, Alycia; Souza, Donald; Jiang, Huiping; Nabozny, Gerald; Modis, Louise Kelly

    2013-01-01

    Vascular adhesion protein-1 (VAP-1) has been implicated in the pathogenesis of inflammatory diseases and is suggested to play a role in immune cell trafficking. It is not clear whether this effect is mediated by the oxidase activity or by other features of the protein such as direct adhesion. In order to study the role of VAP-1 oxidase activity in vivo, we have generated mice carrying an oxidase activity-null VAP-1 protein. We demonstrate that the VAP-1 oxidase null mutant mice have a phenotype similar to the VAP-1 null mice in animal models of sterile peritonitis and antibody induced arthritis suggesting that the oxidase activity is responsible for the inflammatory function of VAP-1.

  13. The oxidase activity of vascular adhesion protein-1 (VAP-1) is essential for function

    PubMed Central

    Noonan, Thomas; Lukas, Susan; Peet, Gregory W; Pelletier, Josephine; Panzenbeck, Mark; Hanidu, Adedayo; Mazurek, Suzanne; Wasti, Ruby; Rybina, Irina; Roma, Teresa; Kronkaitis, Anthony; Shoultz, Alycia; Souza, Donald; Jiang, Huiping; Nabozny, Gerald; Modis, Louise Kelly

    2013-01-01

    Vascular adhesion protein-1 (VAP-1) has been implicated in the pathogenesis of inflammatory diseases and is suggested to play a role in immune cell trafficking. It is not clear whether this effect is mediated by the oxidase activity or by other features of the protein such as direct adhesion. In order to study the role of VAP-1 oxidase activity in vivo, we have generated mice carrying an oxidase activity-null VAP-1 protein. We demonstrate that the VAP-1 oxidase null mutant mice have a phenotype similar to the VAP-1 null mice in animal models of sterile peritonitis and antibody induced arthritis suggesting that the oxidase activity is responsible for the inflammatory function of VAP-1. PMID:23885334

  14. Mechanical and water soaking properties of medium density fiberboard with wood fiber and soybean protein adhesive.

    PubMed

    Li, Xin; Li, Yonghui; Zhong, Zhikai; Wang, Donghai; Ratto, Jo A; Sheng, Kuichuan; Sun, Xiuzhi Susan

    2009-07-01

    Soybean protein is a renewable and abundant material that offers an alternative to formaldehyde-based resins. In this study, soybean protein was modified with sodium dodecyl sulfate (SDS) as an adhesive for wood fiber medium density fiberboard (MDF) preparation. Second-order response surface regression models were used to study the effects and interactions of initial moisture content (IMC) of coated wood fiber, press time (PT) and temperature on mechanical and water soaking properties of MDF. Results showed that IMC of coated fiber was the dominant influencing factor. Mechanical and soaking properties improved as IMC increased and reached their highest point at an IMC of 35%. Press time and temperature also had a significant effect on mechanical and water soaking properties of MDF. Second-order regression results showed that there were strong relationships between mechanical and soaking properties of MDF and processing parameters. Properties of MDF made using soybean protein adhesive are similar to those of commercial board.

  15. Expression of multiple proteins in transgenic plants

    DOEpatents

    Vierstra, Richard D.; Walker, Joseph M.

    2002-01-01

    A method is disclosed for the production of multiple proteins in transgenic plants. A DNA construct for introduction into plants includes a provision to express a fusion protein of two proteins of interest joined by a linking domain including plant ubiquitin. When the fusion protein is produced in the cells of a transgenic plant transformed with the DNA construction, native enzymes present in plant cells cleave the fusion protein to release both proteins of interest into the cells of the transgenic plant. Since the proteins are produced from the same fusion protein, the initial quantities of the proteins in the cells of the plant are approximately equal.

  16. Altered expression of adhesion molecules on peripheral blood leukocytes in feline infectious peritonitis.

    PubMed

    Olyslaegers, Dominique A J; Dedeurwaerder, Annelike; Desmarets, Lowiese M B; Vermeulen, Ben L; Dewerchin, Hannah L; Nauwynck, Hans J

    2013-10-25

    Feline infectious peritonitis (FIP) is a fatal, coronavirus-induced systemic disease in domestic and wild felids. The pathology associated with FIP (multifocal granulomatous vasculitis) is considered to be elicited by exaggerated activation and subsequent extravasation of leukocytes. As changes in the expression of adhesion molecules on circulating leukocytes precede their margination and emigration, we reasoned that the expression of leukocyte adhesion molecules may be altered in FIP. In present study, the expression of principal adhesion molecules involved in leukocyte transmigration (CD15s, CD11a, CD11b, CD18, CD49d, and CD54) on peripheral blood leukocytes from cats with naturally occurring FIP (n=15) and controls (n=12) was quantified by flow cytometry using a formaldehyde-based rapid leukocyte preparation technique. T- and B-lymphocytes from FIP patients exhibit higher expression of both subunits (CD11a and CD18) composing the β2 integrin lymphocyte function-associated antigen (LFA)-1. In addition, the expression of the α4 subunit (CD49d) of the β1 integrin very late antigen (VLA)-4 was elevated on B-lymphocytes from FIP patients. The expression of CD11b and CD18, that combine to form the β2 integrin macrophage-1 antigen (Mac-1), was elevated on monocytes, whereas the density of CD49d was reduced on this population in FIP. Granulocytes of FIP cats displayed an increased expression of the α chain of Mac-1 (CD11b). These observations suggest that leukocytes from FIP patients show signs of systemic activation causing them to extravasate into surrounding tissues and ultimately contribute to pyogranuloma formation seen in FIP.

  17. GPR133 (ADGRD1), an adhesion G-protein-coupled receptor, is necessary for glioblastoma growth

    PubMed Central

    Bayin, N S; Frenster, J D; Kane, J R; Rubenstein, J; Modrek, A S; Baitalmal, R; Dolgalev, I; Rudzenski, K; Scarabottolo, L; Crespi, D; Redaelli, L; Snuderl, M; Golfinos, J G; Doyle, W; Pacione, D; Parker, E C; Chi, A S; Heguy, A; MacNeil, D J; Shohdy, N; Zagzag, D; Placantonakis, D G

    2016-01-01

    Glioblastoma (GBM) is a deadly primary brain malignancy with extensive intratumoral hypoxia. Hypoxic regions of GBM contain stem-like cells and are associated with tumor growth and angiogenesis. The molecular mechanisms that regulate tumor growth in hypoxic conditions are incompletely understood. Here, we use primary human tumor biospecimens and cultures to identify GPR133 (ADGRD1), an orphan member of the adhesion family of G-protein-coupled receptors, as a critical regulator of the response to hypoxia and tumor growth in GBM. GPR133 is selectively expressed in CD133+ GBM stem cells (GSCs) and within the hypoxic areas of PPN in human biospecimens. GPR133 mRNA is transcriptionally upregulated by hypoxia in hypoxia-inducible factor 1α (Hif1α)-dependent manner. Genetic inhibition of GPR133 with short hairpin RNA reduces the prevalence of CD133+ GSCs, tumor cell proliferation and tumorsphere formation in vitro. Forskolin rescues the GPR133 knockdown phenotype, suggesting that GPR133 signaling is mediated by cAMP. Implantation of GBM cells with short hairpin RNA-mediated knockdown of GPR133 in the mouse brain markedly reduces tumor xenograft formation and increases host survival. Analysis of the TCGA data shows that GPR133 expression levels are inversely correlated with patient survival. These findings indicate that GPR133 is an important mediator of the hypoxic response in GBM and has significant protumorigenic functions. We propose that GPR133 represents a novel molecular target in GBM and possibly other malignancies where hypoxia is fundamental to pathogenesis. PMID:27775701

  18. Parathyroid hormone-related protein (PTHrP) modulates adhesion, migration and invasion in bone tumor cells.

    PubMed

    Mak, Isabella W Y; Turcotte, Robert E; Ghert, Michelle

    2013-07-01

    Parathyroid-hormone-related protein (PTHrP) has been shown to be an important factor in osteolysis in the setting of metastatic carcinoma to the bone. However, PTHrP may also be central in the setting of primary bone tumors. Giant cell tumor of bone (GCT) is an aggressive osteolytic bone tumor characterized by osteoclast-like giant cells that are recruited by osteoblast-like stromal cells. The stromal cells of GCT are well established as the only neoplastic element of the tumor, and we have previously shown that PTHrP is highly expressed by these cells both in vitro and in vivo. We have also found that the stromal cells exposed to a monoclonal antibody to PTHrP exhibited rapid plate detachment and quickly died in vitro. Therefore, PTHrP may serve in an autocrine manner to increase cell proliferation and promote invasive properties in GCT. The purpose of this study was to use transcriptomic microarrays and functional assays to examine the effects of PTHrP neutralization on cell adhesion, migration and invasion. Microarray and proteomics data identified genes that were differentially expressed in GCT stromal cells under various PTHrP treatment conditions. Treatment of GCT stromal cells with anti-PTHrP antibodies showed a change in the expression of 13 genes from the integrin family relative to the IgG control. Neutralization of PTHrP reduced cell migration and invasion as evidenced by functional assays. Adhesion and anoikis assays demonstrated that although PTHrP neutralization inhibits cell adhesion properties, cell detachment related to PTHrP neutralization did not result in associated cell death, as expected in mesenchymal stromal cells. Based on the data presented herein, we conclude that PTHrP excreted by GCT stromal cells increases bone tumor cell local invasiveness and migration.

  19. OmpA-like protein influences cell shape and adhesive activity of Tannerella forsythia.

    PubMed

    Abe, T; Murakami, Y; Nagano, K; Hasegawa, Y; Moriguchi, K; Ohno, N; Shimozato, K; Yoshimura, F

    2011-12-01

    Tannerella forsythia, a gram-negative fusiform rod, is implicated in several types of oral anaerobic infections. Most gram-negative bacteria have OmpA-like proteins that are homologous to the OmpA protein in Escherichia coli. We identified an OmpA-like protein in T. forsythia encoded by the tf1331 gene as one of the major proteins by mass spectrometric analysis. Two-dimensional, diagonal electrophoresis showed that the OmpA-like protein formed a dimeric or trimeric structure via intermolecular disulfide bonds. A biotin labeling experiment revealed that a portion of the protein was exposed on the cell surface, even though T. forsythia possesses an S-layer at the outermost cell surface. Using a tf1331-deletion mutant, we showed that the OmpA-like protein affected cell morphology. The length of the mutant cell was reduced almost by half. Cell swelling was observed in more than 40% of the mutant cells. Moreover, the mutant exhibited decreased adhesion to fibronectin, retarded autoaggregation, and reduced cell surface hydrophobicity. These results suggest that the OmpA-like protein in T. forsythia plays an important role in cellular integrity and adhesive function.

  20. Inhalation of ultrafine particles alters blood leukocyte expression of adhesion molecules in humans.

    PubMed

    Frampton, Mark W; Stewart, Judith C; Oberdörster, Günter; Morrow, Paul E; Chalupa, David; Pietropaoli, Anthony P; Frasier, Lauren M; Speers, Donna M; Cox, Christopher; Huang, Li-Shan; Utell, Mark J

    2006-01-01

    Ultrafine particles (UFPs; aerodynamic diameter < 100 nm) may contribute to the respiratory and cardiovascular morbidity and mortality associated with particulate air pollution. We tested the hypothesis that inhalation of carbon UFPs has vascular effects in healthy and asthmatic subjects, detectable as alterations in blood leukocyte expression of adhesion molecules. Healthy subjects inhaled filtered air and freshly generated elemental carbon particles (count median diameter approximately 25nm, geometric standard deviation approximately 1.6), for 2 hr, in three separate protocols: 10 microg/m3 at rest, 10 and 25 microg/m3 with exercise, and 50 microg/m3 with exercise. In a fourth protocol, subjects with asthma inhaled air and 10 microg/m3 UFPs with exercise. Peripheral venous blood was obtained before and at intervals after exposure, and leukocyte expression of surface markers was quantitated using multiparameter flow cytometry. In healthy subjects, particle exposure with exercise reduced expression of adhesion molecules CD54 and CD18 on monocytes and CD18 and CD49d on granulocytes. There were also concentration-related reductions in blood monocytes, basophils, and eosinophils and increased lymphocyte expression of the activation marker CD25. In subjects with asthma, exposure with exercise to 10 microg/m3 UFPs reduced expression of CD11b on monocytes and eosinophils and CD54 on granulocytes. Particle exposure also reduced the percentage of CD4+ T cells, basophils, and eosinophils. Inhalation of elemental carbon UFPs alters peripheral blood leukocyte distribution and expression of adhesion molecules, in a pattern consistent with increased retention of leukocytes in the pulmonary vascular bed.

  1. Expression of metadherin/AEG-1 gene is positively related to orientation chemotaxis and adhesion of human hepatocellular carcinoma cell lines of different metastatic potentials.

    PubMed

    Zhou, Zhenzhen; Deng, Huan; Yan, Wei; Huang, Huanjun; Deng, Yueling; Li, Yuan; Tian, De'an

    2012-06-01

    Metastasis contributes to the poor prognosis of hepatocellular carcinoma (HCC). However, the mechanism through which a primary HCC cell develops into a metastatic phenotype is not well understood. The purpose of this study was to examine the correlation between metadherin (MTDH)/astrocyte elevated gene-1 (AEG-1) expression in HCC cell lines of different metastatic potentials and such metastatic phenotypes as orientation chemotaxis and adhesion. MTDH/AEG-1 expression was detected by RT-PCR and western blotting in HCC cell lines (HepG2, Huh7, Sk-HEP-1, MHCC-97H). Distribution of MTDH/AEG-1 was observed by immunofluorescence staining and confocal laser scanning microscopy. The abilities of orientation chemotaxis and adhesion and the index of interaction between HCC cell lines and microvascular endothelial cell lines (MVECs, including HUVECs and HPMECs) were measured by chemotaxis assay and adhesion assay, respectively. The results showed that MTDH/AEG-1 protein expression was significantly higher in high metastatic potential cancer cell lines (Sk-HEP-1, MHCC-97H) than in low metastatic potential cell lines (HepG2, Huh7) (P<0.05). The MTDH/AEG-1 protein was localized in the perinuclear region of HCC cells. Furthermore, the abilities of orientation chemotaxis and adhesion of HCC cells to HPMECs were increased as compared with those of HCC cells to HUVECs (P<0.05). The abilities of orientation chemotaxis and adhesion were much stronger in Sk-HEP-1 and MHCC-97H cells with MTDH/AEG-1 highly expressed than in HepG2 and Huh7 cells with MTDH/AEG-1 lowly expressed (P<0.05). These results suggested that the expression of MTDH/AEG-1 gene in HCC cell lines of different metastatic potentials was closely positively related to the abilities of orientation chemotaxis and adhesion of HCC cells. It was deduced that MTDH/AEG-1 might play a pivotal role in the lung-specific metastasis of HCC, which may be mediated through orientation chemotaxis and adhesion abilities of HCC cells. MTDH

  2. Ubiquitous distribution of salts and proteins in spider glue enhances spider silk adhesion

    NASA Astrophysics Data System (ADS)

    Amarpuri, Gaurav; Chaurasia, Vishal; Jain, Dharamdeep; Blackledge, Todd A.; Dhinojwala, Ali

    2015-03-01

    Modern orb-weaving spiders use micron-sized glue droplets on their viscid silk to retain prey in webs. A combination of low molecular weight salts and proteins makes the glue viscoelastic and humidity responsive in a way not easily achieved by synthetic adhesives. Optically, the glue droplet shows a heterogeneous structure, but the spatial arrangement of its chemical components is poorly understood. Here, we use optical and confocal Raman microscopy to show that salts and proteins are present ubiquitously throughout the droplet. The distribution of adhesive proteins in the peripheral region explains the superior prey capture performance of orb webs as it enables the entire surface area of the glue droplet to act as a site for prey capture. The presence of salts throughout the droplet explains the recent Solid-State NMR results that show salts directly facilitate protein mobility. Understanding the function of individual glue components and the role of the droplet's macro-structure can help in designing better synthetic adhesives for humid environments.

  3. Mussel adhesive protein provides cohesive matrix for collagen type-1α.

    PubMed

    Martinez Rodriguez, Nadine R; Das, Saurabh; Kaufman, Yair; Wei, Wei; Israelachvili, Jacob N; Waite, J Herbert

    2015-05-01

    Understanding the interactions between collagen and adhesive mussel foot proteins (mfps) can lead to improved medical and dental adhesives, particularly for collagen-rich tissues. Here we investigated interactions between collagen type-1, the most abundant load-bearing animal protein, and mussel foot protein-3 (mfp-3) using a quartz crystal microbalance and surface forces apparatus (SFA). Both hydrophilic and hydrophobic variants of mfp-3 were exploited to probe the nature of the interaction between the protein and collagen. Our chief findings are: 1) mfp-3 is an effective chaperone for tropocollagen adsorption to TiO2 and mica surfaces; 2) at pH 3, collagen addition between two mfp-3 films (Wc = 5.4 ± 0.2 mJ/m(2)) increased their cohesion by nearly 35%; 3) oxidation of Dopa in mfp-3 by periodate did not abolish the adhesion between collagen and mfp-3 films, and 4) collagen bridging between both hydrophilic and hydrophobic mfp-3 variant films is equally robust, suggesting that hydrophobic interactions play a minor role. Extensive H-bonding, π-cation and electrostatic interactions are more plausible to explain the reversible bridging of mfp-3 films by collagen.

  4. Extracellular matrix protein patterns guide human chondrocytes adhesion and alignment characterized by vimentin and matrilin-3.

    PubMed

    Pan, Chang-Jiang; Ding, Hong-Yan; Dong, Yun-Xiao

    2013-02-01

    The main purpose of the present study is to investigate the influences of collagen VI (col-VI) patterns on human chondrocytes behaviors. To this end, col-VI stripes with varying width and interstripe spacing are created on polystyrene (PS) surfaces by microcontact printing (μCP). Human chondrocytes are then seeded on these protein patterns and the cell adhesion and alignment are investigated by staining the vimentin and matrilin-3 secreted by seeded chondrocytes. The results indicate that the cells preferentially attach onto the protein areas, rendering cell patterns and the elongated cell shapes. The pattern dimensions can significantly influence cell adhesion, spreading and orientation. The stripe protein patterns can guide cell adhesion and alignment. The cell morphologies can be controlled by carefully designing the pattern shapes and sizes. Our results suggest that the protein patterns can be used to modify biomaterials' surfaces for selective cell-binding and cell alignment. It could provide some cues for the development of novel implantable biomaterials, such as tissue-engineered scaffolds for cartilage replacement, where specific cell alignment is needed.

  5. SpyAD, a moonlighting protein of group A Streptococcus contributing to bacterial division and host cell adhesion.

    PubMed

    Gallotta, Marilena; Gancitano, Giovanni; Pietrocola, Giampiero; Mora, Marirosa; Pezzicoli, Alfredo; Tuscano, Giovanna; Chiarot, Emiliano; Nardi-Dei, Vincenzo; Taddei, Anna Rita; Rindi, Simonetta; Speziale, Pietro; Soriani, Marco; Grandi, Guido; Margarit, Immaculada; Bensi, Giuliano

    2014-07-01

    Group A streptococcus (GAS) is a human pathogen causing a wide repertoire of mild and severe diseases for which no vaccine is yet available. We recently reported the identification of three protein antigens that in combination conferred wide protection against GAS infection in mice. Here we focused our attention on the characterization of one of these three antigens, Spy0269, a highly conserved, surface-exposed, and immunogenic protein of unknown function. Deletion of the spy0269 gene in a GAS M1 isolate resulted in very long bacterial chains, which is indicative of an impaired capacity of the knockout mutant to properly divide. Confocal microscopy and immunoprecipitation experiments demonstrated that the protein was mainly localized at the cell septum and could interact in vitro with the cell division protein FtsZ, leading us to hypothesize that Spy0269 is a member of the GAS divisome machinery. Predicted structural domains and sequence homologies with known streptococcal adhesins suggested that this antigen could also play a role in mediating GAS interaction with host cells. This hypothesis was confirmed by showing that recombinant Spy0269 could bind to mammalian epithelial cells in vitro and that Lactococcus lactis expressing Spy0269 on its cell surface could adhere to mammalian cells in vitro and to mice nasal mucosa in vivo. On the basis of these data, we believe that Spy0269 is involved both in bacterial cell division and in adhesion to host cells and we propose to rename this multifunctional moonlighting protein as SpyAD (Streptococcus pyogenes Adhesion and Division protein).

  6. Temporal gene expression profile of human precursor B leukemia cells induced by adhesion receptor: identification of pathways regulating B-cell survival.

    PubMed

    Astier, Anne Laurence; Xu, Ronghui; Svoboda, Marek; Hinds, Esther; Munoz, Olivier; de Beaumont, Rosalie; Crean, Colin Daniel; Gabig, Theodore; Freedman, Arnold Stephen

    2003-02-01

    The physical interactions between B cells and stromal cells from the lymphoid tissue microenvironment are critical to the survival of normal and malignant B cells. They are principally mediated by integrins expressed on B cells and counterreceptors on stromal cells. Specifically, alpha4beta1 integrin engagement rescues B cells from physiological or drug-induced apoptosis. Therefore, in order to understand the mechanisms by which integrins prevent apoptosis in leukemia B cells, we compared the temporal gene expression profiles induced by beta1-integrin ligation with fibronectin (Fn) or adhesion by poly-L-Lysine in serum-starved precursor B leukemia cells. Among the 38 selected differentially expressed genes, 6 genes involved in adhesion (VAV2, EPB41L1, CORO1A), proliferation (FRAP1, CCT4), and intercellular communication (GJB3) were validated by real-time quantitative polymerase chain reaction (RT-Q-PCR). Gene expression modulation could also be validated at the protein level for 5 other genes. We show that integrin stimulation up-regulated FBI-1 expression but inhibited CD79a, Requiem, c-Fos, and caspase 7 induction when the cells underwent apoptosis. We further demonstrate that Fn stimulation also inhibits caspase 3 activation but increases XIAP and survivin expression. Moreover, integrin stimulation also prevents caspase activation induced by doxorubicin. Therefore, we identified genes modulated by adhesion of human precursor B leukemia cells that regulate proliferation and apoptosis, highlighting new pathways that might provide insights into future therapy aiming at targeting apoptosis of leukemia cells.

  7. Application of tung oil to improve adhesion strength and water resistance of cottonseed meal and protein adhesives on maple veneer

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Cottonseed meal-based products show promise in serving as environment-friendly wood adhesives. However, their practical utilization is currently limited due to low durability and water resistant properties. In this research, we tested the improvement of adhesion strength and water resistance of cott...

  8. Host tissue response by the expression of collagen to cyanoacrylate adhesives used in implant fixation for abdominal hernia repair.

    PubMed

    Pascual, Gemma; Rodríguez, Marta; Pérez-Köhler, Bárbara; Mesa-Ciller, Claudia; Fernández-Gutiérrez, Mar; San Román, Julio; Bellón, Juan M

    2017-04-01

    The less traumatic use of surgical adhesives rather than sutures for mesh fixation in hernia repair has started to gain popularity because they induce less host tissue damage and provoke less postoperative pain. This study examines the host tissue response to a new cyanoacrylate (CA) adhesive (n-octyl, OCA). Partial defects (3 × 5 cm) created in the rabbit anterior abdominal wall were repaired by mesh fixation using OCA, Glubran2(®)(n-butyl-CA), Ifabond(®)(n-hexyl-CA) or sutures. Samples were obtained at 14/90 days for morphology, collagens qRT-PCR/immunofluorescence and biomechanical studies. All meshes were successfully fixed. Seroma was detected mainly in the Glubran group at 14 days. Meshes fixed using all methods showed good host tissue incorporation. No signs of degradation of any of the adhesives were observed. At 14 days, collagen 1 and 3 mRNA expression levels were greater in the suture and OCA groups, and lower in Ifabond, with levels varying significantly in the latter group with respect to the others. By 90 days, expression levels had fallen in all groups, except for collagen 3 mRNA in Ifabond. Collagen I and III protein expression was marked in the suture and OCA groups at 90 days, but lower in Ifabond at both time points. Tensile strengths were similar across groups. Our findings indicate the similar behavior of the adhesives to sutures in terms of good tissue incorporation of the meshes and optimal repair zone strength. The lower seroma rate and similar collagenization to controls induced by OCA suggests its improved behavior over the other two glues. This article deals with a preclinical study to examine different aspects of the repair process in the host of three alkyl cyanoacrylates (n-butyl (GLUBRAN 2), n-hexyl (IFABOND), and n-octyl cyanoacrylate (EVOBOND)) compared to sutures (control), in the fixation of surgical meshes for hernia repair. It goes into detail about collagen deposition in the repair zone at short and medium term. The

  9. Coevolution of gene expression among interacting proteins

    SciTech Connect

    Fraser, Hunter B.; Hirsh, Aaron E.; Wall, Dennis P.; Eisen,Michael B.

    2004-03-01

    Physically interacting proteins or parts of proteins are expected to evolve in a coordinated manner that preserves proper interactions. Such coevolution at the amino acid-sequence level is well documented and has been used to predict interacting proteins, domains, and amino acids. Interacting proteins are also often precisely coexpressed with one another, presumably to maintain proper stoichiometry among interacting components. Here, we show that the expression levels of physically interacting proteins coevolve. We estimate average expression levels of genes from four closely related fungi of the genus Saccharomyces using the codon adaptation index and show that expression levels of interacting proteins exhibit coordinated changes in these different species. We find that this coevolution of expression is a more powerful predictor of physical interaction than is coevolution of amino acid sequence. These results demonstrate previously uncharacterized coevolution of gene expression, adding a different dimension to the study of the coevolution of interacting proteins and underscoring the importance of maintaining coexpression of interacting proteins over evolutionary time. Our results also suggest that expression coevolution can be used for computational prediction of protein protein interactions.

  10. Protein Adhesion and Ion Substitution (on/in)to Minerals

    NASA Astrophysics Data System (ADS)

    Charlet, L.; Fernandez Martinez, A.; Chapron, Y.; Sahai, N.; Cuello, G.; Brendle, J.; Marichal, C.

    2008-12-01

    Arsenic and pathogenic prion protein-scrapie (PrPsc) are important contaminants which may soil and water for decades, unless they are removed by sorption. Two sorption mechanisms will be discussed, namely the organics (Prp and single aminoacid) adsorption on clay and the arsenic substitution in gypsum. The elucidation of these contrasted mechanisms will be shown to request complementary molecular-mechanical simulations with experimental spectroscopic investigations. As first example, structural studies performed at ILL/ESRF on As-doped gypsum (CaSO4 2H2O) using neutron and X-ray diffraction data and EXAFS were performed to determine how As fits into the bulk of gypsum structure. The combined Rietveld analysis of neutron and X-ray diffraction data shows an expansion of the unit cell volume proportional to the As concentration within the samples. to-sulfate substitution mechanisms were used as simulation starting hypotheses. DFT-based simulations (Mulliken analysis) were used to interpret charge distribution and to show that among the possible mechanisms, a sulphate substitution by either protonated, or fully deprotonated, arsenate ion, only the protonated arsenate substitution could best fit the EXAFS data. In the second example, we used Molecular Dynamics to understand the mechanism of strong binding of the pathogenic PrP peptide with clay mineral surfaces. We modeled only the infectious moiety, PrP92-138, of the whole PrPsc structure, with explicitly solvating water molecules in contact with the cleavage plane of pyrophillite, as a model for montmorillonite without any cationic substitution. Partial residual negative charges on the cleavage plane were balanced with K+ ions. The peptide anchored to the clay surface via up to 10 hydrogen bonds from lysine and histidine residues to oxygen atoms of the siloxane cavities, and a total adsorption energy of 3465 KJ.mol-1 was obtained. Our results were compared to the one obtained by chemical and thermal analysis, 23Na, 1H

  11. Adhesion of phospholipid vesicles to Chinese hamster fibroblasts: Role of cell surface proteins

    PubMed Central

    Pagano, RE; Takeichi, M

    1977-01-01

    The adhesion of artificially generated lipid membrane vesicles to Chinese hamster V79 fibroblasts in suspension was used as a model system for studying membrane interactions. Below their gel-liquid crystalline phase transition temperature, vesicles comprised of dipalmitoyl lecithin (DPL) or dimyristoyl lecithin (DML) absorbed to the surfaces of EDTA- dissociated cells. These adherent vesicles could not be removed by repeated washings of the treated cells but could be released into the medium by treatment with trypsin. EM autoradiographic studies of cells treated with[(3)H]DML or [(3)H]DPL vesicles showed that most of the radioactive lipids were confined to the cell periphery. Scanning electron microscopy and fluorescence microscopy further confirmed the presence of adherent vesicles at the cell surface. Adhesion of DML or DPL vesicles to EDTA-dissociated cells modified the lactoperoxidase-catalyzed iodination pattern of the cell surface proteins; the inhibition of labeling of two proteins with an approximately 60,000- dalton mol wt was particularly evident. Incubation of cells wit h (3)H-lipid vesicles followed by sodium dodecyl sulfate (SDS)- polyacrylamide gel electrophoresis showed that some of the (3)H-lipid migrated preferentially with these approximately 60,000-mol wt proteins. Studies of the temperature dependence of vesicle uptake and subsequent release by trypsin showed that DML or DPL vesicle adhesion to EDTA- dissociated cells increased with decreasing temperatures. In contrast, cells trypsinized before incubation with vesicles showed practically no temperature dependence of vesicle uptake. These results suggest two pathways for adhesion of lipid vesicles to the cell surface-a temperature-sensitive one involving cell surface proteins, and a temperature-independent one. These findings are discussed in terms of current models for cell-cell interactions. PMID:407233

  12. Lowered Expression of Tumor Suppressor Candidate MYO1C Stimulates Cell Proliferation, Suppresses Cell Adhesion and Activates AKT

    PubMed Central

    Visuttijai, Kittichate; Pettersson, Jennifer; Mehrbani Azar, Yashar; van den Bout, Iman; Örndal, Charlotte; Marcickiewicz, Janusz; Nilsson, Staffan; Hörnquist, Michael; Olsson, Björn; Ejeskär, Katarina

    2016-01-01

    Myosin-1C (MYO1C) is a tumor suppressor candidate located in a region of recurrent losses distal to TP53. Myo1c can tightly and specifically bind to PIP2, the substrate of Phosphoinositide 3-kinase (PI3K), and to Rictor, suggesting a role for MYO1C in the PI3K pathway. This study was designed to examine MYO1C expression status in a panel of well-stratified endometrial carcinomas as well as to assess the biological significance of MYO1C as a tumor suppressor in vitro. We found a significant correlation between the tumor stage and lowered expression of MYO1C in endometrial carcinoma samples. In cell transfection experiments, we found a negative correlation between MYO1C expression and cell proliferation, and MYO1C silencing resulted in diminished cell migration and adhesion. Cells expressing excess of MYO1C had low basal level of phosphorylated protein kinase B (PKB, a.k.a. AKT) and cells with knocked down MYO1C expression showed a quicker phosphorylated AKT (pAKT) response in reaction to serum stimulation. Taken together the present study gives further evidence for tumor suppressor activity of MYO1C and suggests MYO1C mediates its tumor suppressor function through inhibition of PI3K pathway and its involvement in loss of contact inhibition. PMID:27716847

  13. Heterologous expression of Streptococcus mutans Cnm in Lactococcus lactis promotes intracellular invasion, adhesion to human cardiac tissues and virulence.

    PubMed

    Freires, Irlan A; Avilés-Reyes, Alejandro; Kitten, Todd; Simpson-Haidaris, P J; Swartz, Michael; Knight, Peter A; Rosalen, Pedro L; Lemos, José A; Abranches, Jacqueline

    2017-01-02

    In S. mutans, the expression of the surface glycoprotein Cnm mediates binding to extracellular matrix proteins, endothelial cell invasion and virulence in the Galleria mellonella invertebrate model. To further characterize Cnm as a virulence factor, the cnm gene from S. mutans strain OMZ175 was expressed in the non-pathogenic Lactococcus lactis NZ9800 using a nisin-inducible system. Despite the absence of the machinery necessary for Cnm glycosylation, Western blot and immunofluorescence microscopy analyses demonstrated that Cnm was effectively expressed and translocated to the cell wall of L. lactis. Similar to S. mutans, expression of Cnm in L. lactis enabled robust binding to collagen and laminin, invasion of human coronary artery endothelial cells and increased virulence in G. mellonella. Using an ex vivo human heart tissue colonization model, we showed that Cnm-positive strains of either S. mutans or L. lactis outcompete their Cnm-negative counterparts for tissue colonization. Finally, Cnm expression facilitated L. lactis adhesion and colonization in a rabbit model of infective endocarditis. Collectively, our results provide unequivocal evidence that binding to extracellular matrices mediated by Cnm is an important virulence attribute of S. mutans and confirm the usefulness of the L. lactis heterologous system for further characterization of bacterial virulence factors.

  14. PI3K/Akt pathway restricts epithelial adhesion of Dr+ Escherichia coli by down-regulating the expression of Decay Accelerating Factor (DAF)

    PubMed Central

    Banadakoppa, Manu; Goluszko, Pawel; Liebenthal, Daniel; Nowicki, Bogdan J.; Nowicki, Stella; Yallampalli, Chandra

    2014-01-01

    The urogenital microbial infection in pregnancy is an important cause of maternal and neonatal morbidity and mortality. Uropathogenic Escherichia coli strains which express Dr fimbriae (Dr+) are associated with unique gestational virulence and they utilize cell surface decay accelerating factor (DAF or CD55) as one of the cellular receptor before invading the epithelial cells. Previous studies in our laboratory established that nitric oxide reduces the rate of E. coli invasion by delocalizing the DAF protein from cell surface lipid rafts and down-regulating its expression. The phosphoinositide 3-kinase/ protein kinase B (PI3K/Akt) cell signal pathway plays an important role in host-microbe interaction because many bacteria including E. coli activate this pathway in order to establish infection. In the present study we showed that the PI3K/Akt pathway negatively regulates the expression of DAF on the epithelial cell surface and thus inhibits the adhesion of Dr+ E. coli to epithelial cells. Initially, using two human cell lines Ishikawa and HeLa which differ in constitutive activity of PI3K/Akt we showed that DAF levels were associated with the PI3K/Akt pathway. We then showed that the DAF gene expression was up-regulated and the Dr+ E. coli adhesion increased after the suppression of PI3K/Akt pathway in Ishikawa cells using inhibitor LY-294002, and a plasmid which allowed the expression of PI3K/Akt regulatory protein PTEN. The down-regulation of PTEN protein using PTEN-specific siRNA activated the PI3K/Akt pathway, down-regulated the DAF and decreased the adhesion of Dr+ E. coli. We conclude that the PI3K/Akt pathway regulated the DAF expression in a nitric oxide independent manner. PMID:24599886

  15. DDB2 (damaged-DNA binding 2) protein: a new modulator of nanomechanical properties and cell adhesion of breast cancer cells

    NASA Astrophysics Data System (ADS)

    Barbieux, Claire; Bacharouche, Jalal; Soussen, Charles; Hupont, Sébastien; Razafitianamaharavo, Angélina; Klotz, Rémi; Pannequin, Rémi; Brie, David; Bécuwe, Philippe; Francius, Grégory; Grandemange, Stéphanie

    2016-02-01

    DDB2, known for its role in DNA repair, was recently shown to reduce mammary tumor invasiveness by inducing the transcription of IκBα, an inhibitor of NF-κB activity. Since cellular adhesion is a key event during the epithelial to mesenchymal transition (EMT) leading to the invasive capacities of breast tumor cells, the aim of this study was to investigate the role of DDB2 in this process. Thus, using low and high DDB2-expressing MDA-MB231 and MCF7 cells, respectively, in which DDB2 expression was modulated experimentally, we showed that DDB2 overexpression was associated with a decrease of adhesion abilities on glass and plastic areas of breast cancer cells. Then, we investigated cell nanomechanical properties by atomic force microscopy (AFM). Our results revealed significant changes in the Young's Modulus value and the adhesion force in MDA-MB231 and MCF7 cells, whether DDB2 was expressed or not. The cell stiffness decrease observed in MDA-MB231 and MCF7 expressing DDB2 was correlated with a loss of the cortical actin-cytoskeleton staining. To understand how DDB2 regulates these processes, an adhesion-related gene PCR-Array was performed. Several adhesion-related genes were differentially expressed according to DDB2 expression, indicating that important changes are occurring at the molecular level. Thus, this work demonstrates that AFM technology is an important tool to follow cellular changes during tumorigenesis. Moreover, our data revealed that DDB2 is involved in early events occurring during metastatic progression of breast cancer cells and will contribute to define this protein as a new marker of metastatic progression in this type of cancer.

  16. DDB2 (damaged-DNA binding 2) protein: a new modulator of nanomechanical properties and cell adhesion of breast cancer cells.

    PubMed

    Barbieux, Claire; Bacharouche, Jalal; Soussen, Charles; Hupont, Sébastien; Razafitianamaharavo, Angélina; Klotz, Rémi; Pannequin, Rémi; Brie, David; Bécuwe, Philippe; Francius, Grégory; Grandemange, Stéphanie

    2016-03-07

    DDB2, known for its role in DNA repair, was recently shown to reduce mammary tumor invasiveness by inducing the transcription of IκBα, an inhibitor of NF-κB activity. Since cellular adhesion is a key event during the epithelial to mesenchymal transition (EMT) leading to the invasive capacities of breast tumor cells, the aim of this study was to investigate the role of DDB2 in this process. Thus, using low and high DDB2-expressing MDA-MB231 and MCF7 cells, respectively, in which DDB2 expression was modulated experimentally, we showed that DDB2 overexpression was associated with a decrease of adhesion abilities on glass and plastic areas of breast cancer cells. Then, we investigated cell nanomechanical properties by atomic force microscopy (AFM). Our results revealed significant changes in the Young's Modulus value and the adhesion force in MDA-MB231 and MCF7 cells, whether DDB2 was expressed or not. The cell stiffness decrease observed in MDA-MB231 and MCF7 expressing DDB2 was correlated with a loss of the cortical actin-cytoskeleton staining. To understand how DDB2 regulates these processes, an adhesion-related gene PCR-Array was performed. Several adhesion-related genes were differentially expressed according to DDB2 expression, indicating that important changes are occurring at the molecular level. Thus, this work demonstrates that AFM technology is an important tool to follow cellular changes during tumorigenesis. Moreover, our data revealed that DDB2 is involved in early events occurring during metastatic progression of breast cancer cells and will contribute to define this protein as a new marker of metastatic progression in this type of cancer.

  17. Adhesion-Linked Protein Tyrosine Phosphatases, Morphogenesis and Breast Cancer Progression

    DTIC Science & Technology

    2006-07-01

    baculoviral expression system to prepare a full length recombinant protein in Sf9 insect cells. We reasoned that expression of such a large protein...baculovirus expressing PTPN4 6 wild type and active site mutants as N terminally six histidine tagged proteins in Sf9 cells to facilitate rapid one step...from infected Sf9 cells from both wild type and active site mutant (band at ~116kDa present only in cells infected with PTPN4 recombinant baculovirus

  18. Regulation of extracellular matrix proteins and integrin cell substratum adhesion receptors on epithelium during cutaneous human wound healing in vivo.

    PubMed Central

    Juhasz, I.; Murphy, G. F.; Yan, H. C.; Herlyn, M.; Albelda, S. M.

    1993-01-01

    Although changes in extracellular matrix proteins during wound healing have been well documented, little is known about the regulation of corresponding extracellular matrix adhesion receptors (integrins). To study this process in a human in vivo model, full thickness human skin grafts were transplanted onto severe combined immunodeficient mice and deep excisional wounds involving both the epidermal and dermal layers were then made. The changes in the expression of cell matrix proteins and epithelial integrins over time were analyzed with specific antibodies using immunohistochemistry. Wounding was associated with alterations in extracellular matrix proteins, namely, loss of laminin and type IV collagen in the region of the wound and expression of tenascin and fibronectin. Changes were also noted in the integrins on the migrating keratinocytes. There was marked up-regulation of the alpha v subunit and de novo expression of the fibronectin receptor (alpha 5 beta 1) during the stage of active migration (days 1 to 3 after wounding). In the later stages of wound healing, after epithelial integrity had been established, redistribution of the alpha 2, alpha 3, alpha 6, and beta 4 collagen/laminin-binding integrin subunits to suprabasal epidermal layers was noted. Thus, during cutaneous wound healing, keratinocytes up-regulate fibronectin/fibrinogen-binding integrins and redistribute collagen/laminin-binding integrins. This study demonstrates that the human skin/severe combined immunodeficient chimera provides a useful model to study events during human wound repair. Images Figure 1 Figure 2 Figure 3 Figure 4 Figure 5 Figure 6 PMID:7694470

  19. Tunable Adsorption and Film Formation of Mussel Adhesive Protein by Potential Control.

    PubMed

    Zhang, Fan; Xie, Guoxin; Pan, Jinshan

    2017-01-23

    Mussel adhesive proteins are of great interest in many applications because of their outstanding adhesive property and film-forming ability. Understanding and controlling the film formation and its performance is crucial for the effective use of such proteins. In this study, we focus on the potential controlled film formation and compaction of one mussel adhesive protein, Mefp-1. The adsorption and film-forming behavior of Mefp-1 on a platinum (Pt) substrate under applied potentials were investigated by cyclic voltammetry, potential-controlled electrochemical impedance spectroscopy (EIS), and quartz crystal microbalance with dissipation monitoring (QCM-D). Moreover, microfriction measurements were performed to evaluate the mechanical properties of the Mefp-1 films formed at selected potentials. The results led to the conclusion that Mefp-1 adsorbs on the Pt substrate through both electrostatic and nonelectrostatic interactions and shows an effective blocking effect for the electroactive sites on the substrate. The properties of the adsorbed Mefp-1 film vary with the applied potential, and the compactness of the adsorbed Mefp-1 film can be reversibly tuned by the applied potential.

  20. An immediate-early protein of white spot syndrome virus modulates the phosphorylation of focal adhesion kinase of shrimp.

    PubMed

    Lu, Huasong; Ruan, Lingwei; Xu, Xun

    2011-10-25

    WSSV interacts with integrin during infection of shrimps and modulate the focal adhesion kinase which is known as a regulator of several downstream signaling pathways. Viral protein kinases are thought to be important for virus infection by regulating the host signaling pathways. WSV083 is an immediate-early gene of white spot syndrome virus that contains a Ser/Thr protein kinase domain. So, does WSSV modulate FAK phosphorylation via the WSV083 molecule? In this study, co-transfection of WSV083 and MjFAK genes proceeded in insect cells revealed that the MjFAK phosphorylation and cell adhesion activity could be inhibited by the expression of WSV083. Kinase domain mutants of WSV083 lost its ability of inhibiting FAK phosphorylation. Moreover, silencing of FAK gene through RNAi accelerated the shrimp death rate upon WSSV challenge. These results demonstrate for the first time that modulation of FAK phosphorylation by WSV083 plays a critical role in the pathogenesis of WSSV infection.

  1. The oxidase activity of vascular adhesion protein-1 (VAP-1) induces endothelial E- and P-selectins and leukocyte binding.

    PubMed

    Jalkanen, Sirpa; Karikoski, Marika; Mercier, Nathalie; Koskinen, Kaisa; Henttinen, Tiina; Elima, Kati; Salmivirta, Katriina; Salmi, Marko

    2007-09-15

    Leukocyte migration from the blood into tissues is pivotal in immune homeostasis and in inflammation. During the multistep extravasation cascade, endothelial selectins (P- and E-selectin) and vascular adhesion protein-1 (VAP-1), a cell-surface-expressed oxidase, are important in tethering and rolling. Here, we studied the signaling functions of the catalytic activity of VAP-1. Using human endothelial cells transfected with wild-type VAP-1 and an enzymatically inactive VAP-1 point mutant, we show that transcription and translation of E- and P-selectins are induced through the enzymatic activity of VAP-1. Moreover, use of VAP-1-deficient animals and VAP-1-deficient animals carrying the human VAP-1 as a transgene show a VAP-enzyme activity-dependent induction of P-selectin in vivo. Up-regulation of P-selectin was found both in high endothelial venules in lymphoid tissues and in flat-walled vessels in noninflamed tissues. VAP-1 activity in vivo led to increased P-selectin-dependent binding of lymphocytes to endothelial cells. These data show that the oxidase reaction catalyzed by VAP-1 alters the expression of other molecules involved in the leukocyte extravasation cascade. Our findings indicate cross-talk between adhesion molecules involved in the tethering and rolling of leukocytes and show that VAP-1-dependent signaling can prime the vessels for an enhanced inflammatory response.

  2. Surface expression of Helicobacter pylori HpaA adhesion antigen on Vibrio cholerae, enhanced by co-expressed enterotoxigenic Escherichia coli fimbrial antigens.

    PubMed

    Tobias, Joshua; Lebens, Michael; Wai, Sun Nyunt; Holmgren, Jan; Svennerholm, Ann-Mari

    2017-02-17

    Helicobacter pylori infection can cause peptic ulceration and is associated with gastric adenocarcinoma. This study aimed to construct and characterize a non-virulent Vibrio cholerae O1 strain, which grows more rapidly than H. pylori, as vector for H. pylori antigens for possible use as a vaccine strain against H. pylori. This was done by recombinant expression of the H. pylori adhesion antigen HpaA alone or, as a proof of principle, together with different colonization factor (CF) antigens of enterotoxigenic Escherichia coli (ETEC) which may enhance immune responses against HpaA. A recombinant V. cholerae strain co-expressing HpaA and a fimbrial CF antigens CFA/I or CS5, but not the non-fimbrial CF protein CS6, was shown to express larger amounts of HpaA on the surface when compared with the same V. cholerae strain expressing HpaA alone. Mutations in the CFA/I operon showed that the chaperon, possibly together with the usher, was involved in enhancing the surface expression of HpaA. Oral immunization of mice with formaldehyde-inactivated recombinant V. cholerae expressing HpaA alone or together with CFA/I induced significantly higher serum antibody responses against HpaA than mice similarly immunized with inactivated HpaA-expressing H. pylori bacteria. Our results demonstrate that a non-virulent V. cholerae strain can be engineered to allow strong surface expression of HpaA, and that the expression can be further increased by co-expressing it with ETEC fimbrial antigens. Such recombinant V. cholerae strains expressing HpaA, and possibly also other H. pylori antigens, may have the potential as oral inactivated vaccine candidates against H. pylori.

  3. Lectin Receptor Kinases Participate in Protein-Protein Interactions to Mediate Plasma Membrane-Cell Wall Adhesions in Arabidopsis1

    PubMed Central

    Gouget, Anne; Senchou, Virginie; Govers, Francine; Sanson, Arnaud; Barre, Annick; Rougé, Pierre; Pont-Lezica, Rafael; Canut, Hervé

    2006-01-01

    Interactions between plant cell walls and plasma membranes are essential for cells to function properly, but the molecules that mediate the structural continuity between wall and membrane are unknown. Some of these interactions, which are visualized upon tissue plasmolysis in Arabidopsis (Arabidopsis thaliana), are disrupted by the RGD (arginine-glycine-aspartic acid) tripeptide sequence, a characteristic cell adhesion motif in mammals. In planta induced-O (IPI-O) is an RGD-containing protein from the plant pathogen Phytophthora infestans that can disrupt cell wall-plasma membrane adhesions through its RGD motif. To identify peptide sequences that specifically bind the RGD motif of the IPI-O protein and potentially play a role in receptor recognition, we screened a heptamer peptide library displayed in a filamentous phage and selected two peptides acting as inhibitors of the plasma membrane RGD-binding activity of Arabidopsis. Moreover, the two peptides also disrupted cell wall-plasma membrane adhesions. Sequence comparison of the RGD-binding peptides with the Arabidopsis proteome revealed 12 proteins containing amino acid sequences in their extracellular domains common with the two RGD-binding peptides. Eight belong to the receptor-like kinase family, four of which have a lectin-like extracellular domain. The lectin domain of one of these, At5g60300, recognized the RGD motif both in peptides and proteins. These results imply that lectin receptor kinases are involved in protein-protein interactions with RGD-containing proteins as potential ligands, and play a structural and signaling role at the plant cell surfaces. PMID:16361528

  4. Lectin receptor kinases participate in protein-protein interactions to mediate plasma membrane-cell wall adhesions in Arabidopsis.

    PubMed

    Gouget, Anne; Senchou, Virginie; Govers, Francine; Sanson, Arnaud; Barre, Annick; Rougé, Pierre; Pont-Lezica, Rafael; Canut, Hervé

    2006-01-01

    Interactions between plant cell walls and plasma membranes are essential for cells to function properly, but the molecules that mediate the structural continuity between wall and membrane are unknown. Some of these interactions, which are visualized upon tissue plasmolysis in Arabidopsis (Arabidopsis thaliana), are disrupted by the RGD (arginine-glycine-aspartic acid) tripeptide sequence, a characteristic cell adhesion motif in mammals. In planta induced-O (IPI-O) is an RGD-containing protein from the plant pathogen Phytophthora infestans that can disrupt cell wall-plasma membrane adhesions through its RGD motif. To identify peptide sequences that specifically bind the RGD motif of the IPI-O protein and potentially play a role in receptor recognition, we screened a heptamer peptide library displayed in a filamentous phage and selected two peptides acting as inhibitors of the plasma membrane RGD-binding activity of Arabidopsis. Moreover, the two peptides also disrupted cell wall-plasma membrane adhesions. Sequence comparison of the RGD-binding peptides with the Arabidopsis proteome revealed 12 proteins containing amino acid sequences in their extracellular domains common with the two RGD-binding peptides. Eight belong to the receptor-like kinase family, four of which have a lectin-like extracellular domain. The lectin domain of one of these, At5g60300, recognized the RGD motif both in peptides and proteins. These results imply that lectin receptor kinases are involved in protein-protein interactions with RGD-containing proteins as potential ligands, and play a structural and signaling role at the plant cell surfaces.

  5. Adhesion-modulating/matricellular ECM protein families: a structural, functional and evolutionary appraisal.

    PubMed

    Mosher, Deane F; Adams, Josephine C

    2012-04-01

    The thrombospondins are a family of secreted, oligomeric glycoproteins that interact with cell surfaces, multiple components of the extracellular matrix, growth factors and proteases. These interactions underlie complex roles in cell interactions and tissue homeostasis in animals. Thrombospondins have been grouped functionally with SPARCs, tenascins and CCN proteins as adhesion-modulating or matricellular components of the extracellular milieu. Although all these multi-domain proteins share various commonalities of domains, the grouping is not based on structural homologies. Instead, the terms emphasise the general observations that these proteins do not form large-scale ECM structures, yet act at cell surfaces and function in coordination with the structural ECM and associated extracellular proteins. The designation of adhesion-modulation thus depends on observed tissue and cell culture ECM distributions and on experimentally identified functional properties. To date, the evolutionary relationships of these proteins have not been critically compared: yet, knowledge of their evolutionary histories is clearly relevant to any consideration of functional similarities. In this article, we survey briefly the structural and functional knowledge of these protein families, consider the evolution of each family, and outline a perspective on their functional roles.

  6. The glue protein of ribbed mussels (Geukensia demissa): a natural adhesive with some features of collagen.

    PubMed

    Waite, J H; Hansen, D C; Little, K T

    1989-01-01

    The Atlantic ribbed mussel Geukensia (Modiolus) demissa attaches itself to the roots of cord grass and other hard objects in tidal salt marshes by spinning adhesive byssal threads. The precursor of a protein apparently present in the adhesive plaques of the threads was isolated in quantity from the foot of the mussel. The protein has an apparent molecular weight of 130,000, a pI of 8.1, and contains a high proportion of Gly, Glu/Gln, Lys and 3,4-dihydroxyphenyl-L-alanine (DOPA). Sequence of tryptic peptides suggests a pattern of repeated motifs, such as: Gly--DOPA--Lys, and X--Gly--DOPA--Y--Z--Gly--DOPA/Tyr--Lys, where X is Thr or Ala in octapeptides and Gln--Thr in nonapeptides. Y is variable, but more often than not hydrophobic; and Z is frequently Pro or 4-trans-hydroxyproline (Hyp). The presence of Pro--Gly and Hyp--Gly sequences of delta-hydroxylysine in the protein is reminiscent of typical collagens; however, the protein is not labile to clostridial collagenase, nor does collagen cross-react with antibodies raised against the mussel protein. Unlike typical collagens, Gly probably occurs only at every 4th or 5th residue in this unusual mussel protein.

  7. Chick neural retina adhesion and survival molecule is a retinol-binding protein

    SciTech Connect

    Schubert, D.; LaCorbiere, M.; Esch, F.

    1986-01-01

    A 20,000-D protein called purpurin has recently been isolated from the growth-conditioned medium of cultured embryonic chick neural retina cells. Purpurin is a constituent of adherons and promotes cell-adheron adhesion by interacting with a cell surface heparan sulfate proteoglycan. It also prolongs the survival of cultured neural retina cells. This paper shows that purpurin is a secretory protein that has sequence homology with a human protein synthesized in the liver that transports retinol in the blood, the serum retinol-binding protein (RBP). Purpurin binds (/sup 3/H)retinol, and both purpurin and chick serum RBP stimulate the adhesion of neural retina cells, although the serum protein is less active than purpurin. Purpurin and the serum RBP are, however, different molecules, for the serum protein is approx.3.000 D larger than purpurin and has different silver-staining characteristics. Finally, purpurin supports the survival of dissociated ciliary ganglion cells, indicating that RBPs can act as ciliary neurotrophic factors.

  8. Neutrophil adhesion molecule expression during cardiopulmonary bypass: a comparative study of roller and centrifugal pumps.

    PubMed

    Macey, M G; McCarthy, D A; Trivedi, U R; Venn, G E; Chambers, D J; Brown, K A

    1997-09-01

    The purpose of this study was to determine whether adhesion molecules and markers of cell activation were preferentially increased on blood neutrophils during cardiopulmonary bypass (CPB) and whether such effects were influenced by the use of a roller pump or a centrifugal pump. Forty-six patients undergoing open heart surgery were randomly allocated into either the roller or centrifugal groups. Blood (1 ml volumes) was removed from arterial and venous lines immediately before and 1 h after the start of bypass. Whole blood samples were immunolabelled and flow cytometry used to measure the distribution and expression of the adhesion molecules CD11b, CD18, CD62L on neutrophils, monocytes and lymphocytes, in addition to CD64 on neutrophils and monocytes, and CD14 on monocytes. The expression of CD11b was significantly enhanced on neutrophils in arterial and venous samples from both the roller pump (mean 84% and 100% increase, respectively; p < 0.001) and centrifugal pump (mean 74% and 73% increase, respectively; p < 0.001) groups. Neutrophil L-selectin expression increased to a small but significant extent in arterial and venous samples from the centrifugal pump group (mean 16% increase; p < 0.001) and in venous samples from the roller pump group (mean 10% increase; p < 0.01). Neither the percentage of neutrophils bearing CD11b/CD18, CD62L and CD64, nor the expression of adhesion molecules on lymphocytes and monocytes were modified by 1 h of bypass. These results suggest that patients subjected to CPB with roller or centrifugal pumps are equally at risk to neutrophil activation that could lead to increased interaction of these cells with blood vessel walls.

  9. PCR arrays indicate that the expression of extracellular matrix and cell adhesion genes in human adipocytes is regulated by IL-1β (interleukin-1β).

    PubMed

    Kępczyńska, Malgorzata A; Zaibi, Mohamed S; Alomar, Suliman Y; Trayhurn, Paul

    2017-02-01

    The role of IL-1β in regulating the expression of extracellular matrix (ECM) and cell adhesion genes in human adipocytes has been examined. Adipocytes differentiated in culture were incubated with IL-1β for 4 or 24 h and RNA probed with PCR arrays for 84 ECM and cell adhesion genes. Treatment with IL-1β resulted in changes in the expression at one or both time points of ∼50% of the genes probed by the arrays, the majority being down-regulated. Genes whose expression was down-regulated by IL-1β included those encoding several collagen chains and integrin subunits. In contrast, IL-1β induced substantial increases (>10-fold) in the expression of ICAM1, VCAM1, MMP1 and MMP3; the secretion of the encoded proteins was also markedly stimulated. IL-1β has a pervasive effect on the expression of ECM and cell adhesion genes in human adipocytes, consistent with the derangement of tissue structure during inflammation in white fat.

  10. Identification of surface proteins involved in the adhesion of a probiotic Bacillus cereus strain to mucin and fibronectin.

    PubMed

    Sánchez, B; Arias, S; Chaignepain, S; Denayrolles, M; Schmitter, J M; Bressollier, P; Urdaci, M C

    2009-05-01

    Several Bacillus strains isolated from commercial probiotic preparations were identified at the species level, and their adhesion capabilities to three different model intestinal surfaces (mucin, Matrigel and Caco-2 cells) were assessed. In general, adhesion of spores was higher than that of vegetative cells to the three matrices, and overall strain Bacillus cereus(CH) displayed the best adhesion. Different biochemical treatments revealed that surface proteins of B. cereus(CH) were involved in the adhesion properties of the strain. Surface-associated proteins from vegetative cells and spores of B. cereus(CH) were extracted and identified, and some proteins such as S-layer components, flagellin and cell-bound proteases were found to bind to mucin or fibronectin. These facts suggest that those proteins might play important roles in the interaction of this probiotic Bacillus strain within the human gastrointestinal tract.

  11. Control of high affinity interactions in the talin C terminus: how talin domains coordinate protein dynamics in cell adhesions.

    PubMed

    Himmel, Mirko; Ritter, Anett; Rothemund, Sven; Pauling, Björg V; Rottner, Klemens; Gingras, Alexandre R; Ziegler, Wolfgang H

    2009-05-15

    In cell-extracellular matrix junctions (focal adhesions), the cytoskeletal protein talin is central to the connection of integrins to the actin cytoskeleton. Talin is thought to mediate this connection via its two integrin, (at least) three actin, and several vinculin binding sites. The binding sites are cryptic in the head-to-rod autoinhibited cytoplasmic form of the protein and require (stepwise) conformational activation. This activation process, however, remains poorly understood, and there are contradictory models with respect to the determinants of adhesion site localization. Here, we report turnover rates and protein-protein interactions in a range of talin rod domain constructs varying in helix bundle structure. We conclude that several bundles of the C terminus cooperate to regulate targeting and concomitantly tailor high affinity interactions of the talin rod in cell adhesions. Intrinsic control of ligand binding activities is essential for the coordination of adhesion site function of talin.

  12. Optimization of intrinsic and extrinsic tendon healing through controllable water-soluble mitomycin-C release from electrospun fibers by mediating adhesion-related gene expression.

    PubMed

    Zhao, Xin; Jiang, Shichao; Liu, Shen; Chen, Shuai; Lin, Zhi Yuan William; Pan, Guoqing; He, Fan; Li, Fengfeng; Fan, Cunyi; Cui, Wenguo

    2015-08-01

    To balance intrinsic and extrinsic healing during tendon repair is challenging in tendon surgery. We hypothesized that by mediating apoptotic gene and collagen synthesis of exogenous fibroblasts, the adhesion formation induced by extrinsic healing could be inhibited. With the maintenance of intrinsic healing, the tendon could be healed with proper function with no adhesion. In this study, we loaded hydrophilic mitomycin-C (MMC) into hyaluronan (HA) hydrosols, which were then encapsulated in poly(L-lactic acid) (PLLA) fibers by micro-sol electrospinning. This strategy successfully provided a controlled release of MMC to inhibit adhesion formations with no detrimental effect on intrinsic healing. We found that micro-sol electrospinning was an effective and facile approach to incorporate and control hydrophilic drug release from hydrophobic polyester fibers. MMC exhibited an initially rapid, and gradually steadier release during 40 days, and the release rates could be tuned by its concentration. In vitro studies revealed that low concentrations of MMC could inhibit fibroblast adhesion and proliferation. When lacerate tendons were healed using the MMC-HA loaded PLLA fibers in vivo, they exhibited comparable mechanical strength to the naturally healed tendons but with no significant presence of adhesion formation. We further identified the up-regulation of apoptotic protein Bax expression and down-regulation of proteins Bcl2, collage I, collagen III and α-SMA during the healing process associated with minimum adhesion formations. This approach presented here leverages new advances in drug delivery and nanotechnology and offers a promising strategy to balance intrinsic and extrinsic tendon healing through modulating genes associated with fibroblast apoptosis and collagen synthesis.

  13. Mapping the dynamics and nanoscale organization of synaptic adhesion proteins using monomeric streptavidin

    PubMed Central

    Chamma, Ingrid; Letellier, Mathieu; Butler, Corey; Tessier, Béatrice; Lim, Kok-Hong; Gauthereau, Isabel; Choquet, Daniel; Sibarita, Jean-Baptiste; Park, Sheldon; Sainlos, Matthieu; Thoumine, Olivier

    2016-01-01

    The advent of super-resolution imaging (SRI) has created a need for optimized labelling strategies. We present a new method relying on fluorophore-conjugated monomeric streptavidin (mSA) to label membrane proteins carrying a short, enzymatically biotinylated tag, compatible with SRI techniques including uPAINT, STED and dSTORM. We demonstrate efficient and specific labelling of target proteins in confined intercellular and organotypic tissues, with reduced steric hindrance and no crosslinking compared with multivalent probes. We use mSA to decipher the dynamics and nanoscale organization of the synaptic adhesion molecules neurexin-1β, neuroligin-1 (Nlg1) and leucine-rich-repeat transmembrane protein 2 (LRRTM2) in a dual-colour configuration with GFP nanobody, and show that these proteins are diffusionally trapped at synapses where they form apposed trans-synaptic adhesive structures. Furthermore, Nlg1 is dynamic, disperse and sensitive to synaptic stimulation, whereas LRRTM2 is organized in compact and stable nanodomains. Thus, mSA is a versatile tool to image membrane proteins at high resolution in complex live environments, providing novel information about the nano-organization of biological structures. PMID:26979420

  14. In vitro investigation of protein adsorption and platelet adhesion on inorganic biomaterial surfaces

    NASA Astrophysics Data System (ADS)

    Huang, Yan; Lü, Xiaoying; Jingwu, Ma; Huang, Nan

    2008-11-01

    The aim of this paper was to study the surface properties, protein adsorption and platelet adhesion behaviors of diamond-like carbon (DLC) and titanium (Ti) films. The surface energy and microstructures of these films were characterized by contact angle measurement and atomic force microscopy (AFM). A modified Coomassie brilliant blue (CBB) protein assay was used to study the amount of adsorbed proteins. Platelet adhesion was assessed by scanning electron microscopy (SEM). The AFM results show that the DLC film is smoother than Ti. Protein adsorption results from CBB protein assay show that the ratio of adsorbed albumin (Alb) to IgG ( RA/I) on DLC is larger than Ti, which coincide with the sequence of the ratio of interfacial tension between solid surface and Alb ( γS,Alb) to interfacial tension between surface and IgG ( γS,IgG) ( γS,Alb/ γS,IgG). The DLC film has a preferential adsorption for Alb. The results suggest that the ratio of γS,Alb/ γS,IgG may indicate an Alb/IgG affinity ratio of materials. More platelets adhere on Ti film than on DLC, which may correspond to the surface roughness of materials. The conclusion is the blood compatibility of DLC seems to be better than Ti.

  15. Bacterial adhesion to protein-coated surfaces: An AFM and QCM-D study

    NASA Astrophysics Data System (ADS)

    Strauss, Joshua; Liu, Yatao; Camesano, Terri A.

    2009-09-01

    Bacterial adhesion to biomaterials, mineral surfaces, or other industrial surfaces is strongly controlled by the way bacteria interact with protein layers or organic matter and other biomolecules that coat the materials. Despite this knowledge, many studies of bacterial adhesion are performed under clean conditions, instead of in the presence of proteins or organic molecules. We chose fetal bovine serum (FBS) as a model protein, and prepared FBS films on quartz crystals. The thickness of the FBS layer was characterized using atomic force microscopy (AFM) imaging under liquid and quartz crystal microbalance with dissipation (QCM-D). Next, we characterized how the model biomaterial surface would interact with the nocosomial pathogen Staphylococcus epidermidis. An AFM probe was coated with S. epidermidis cells and used to probe a gold slide that had been coated with FBS or another protein, fibronectin (FN). These experiments show that AFM and QCM-D can be used in complementary ways to study the complex interactions between bacteria, proteins, and surfaces.

  16. MICA Expression Is Regulated by Cell Adhesion and Contact in a FAK/Src-Dependent Manner

    PubMed Central

    Moncayo, Gerald; Lin, Da; McCarthy, Michael T.; Watson, Aleksandra A.; O’Callaghan, Christopher A.

    2017-01-01

    MICA is a major ligand for the NKG2D immune receptor, which plays a key role in activating natural killer (NK) cells and cytotoxic T cells. We analyzed NKG2D ligand expression on a range of cell types and could demonstrate that MICA expression levels were closely linked to cellular growth mode. While the expression of other NKG2D ligands was largely independent of cell growth mode, MICA expression was mainly found on cells cultured as adherent cells. In addition, MICA surface expression was reduced through increase in cell–cell contact or loss of cell–matrix adherence. Furthermore, we found that the reduction in MICA expression was modulated by focal adhesion kinase (FAK)/Src signaling and associated with increased susceptibility to NK cell-mediated killing. While the mechanisms of tumor immune evasion are not fully understood, the reduction of MICA expression following loss of attachment poises a potential way by which metastasizing tumor cells avoid immune detection. The role of FAK/Src in this process indicates a potential therapeutic approach to modulate MICA expression and immune recognition of tumor cells during metastasis. PMID:28154561

  17. PXL01 in sodium hyaluronate results in increased PRG4 expression: a potential mechanism for anti-adhesion

    PubMed Central

    Edsfeldt, Sara; Holm, Björn; Mahlapuu, Margit; Reno, Carol; Hart, David A.; Wiig, Monica

    2017-01-01

    Purpose To investigate the anti-adhesive mechanisms of PXL01 in sodium hyaluronate (HA) by using the rabbit lactoferrin peptide, rabPXL01 in HA, in a rabbit model of healing tendons and tendon sheaths. The mechanism of action for PXL01 in HA is interesting since a recent clinical study of the human lactoferrin peptide PXL01 in HA administered around repaired tendons in the hand showed improved digit mobility. Materials and methods On days 1, 3, and 6 after tendon injury and surgical repair, reverse transcriptase-quantitative polymerase chain reaction (RT-qPCR) was used to assess mRNA expression levels for genes encoding the mucinous glycoprotein PRG4 (also called lubricin) and a subset of matrix proteins, cytokines, and growth factors involved in flexor tendon repair. RabPXL01 in HA was administered locally around the repaired tendons, and mRNA expression was compared with untreated repaired tendons and tendon sheaths. Results We observed, at all time points, increased expression of PRG4 mRNA in tendons treated with rabPXL01 in HA, but not in tendon sheaths. In addition, treatment with rabPXL01 in HA led to repression of the mRNA levels for the pro-inflammatory mediators interleukin (IL)-1β, IL-6, and IL-8 in tendon sheaths. Conclusions RabPXL01 in HA increased lubricin mRNA production while diminishing mRNA levels of inflammatory mediators, which in turn reduced the gliding resistance and inhibited the adhesion formation after flexor tendon repair. PMID:27658527

  18. Processing of mussel-adhesive protein analog copolymer thin films by matrix-assisted pulsed laser evaporation

    NASA Astrophysics Data System (ADS)

    Patz, T.; Cristescu, R.; Narayan, R.; Menegazzo, N.; Mizaikoff, B.; Messersmith, P. B.; Stamatin, I.; Mihailescu, I. N.; Chrisey, D. B.

    2005-07-01

    We have demonstrated the successful thin film growth of a mussel-adhesive protein analog, DOPA-modified PEO-PPO-PEO block copolymer PF127, using matrix-assisted pulsed laser evaporation (MAPLE). The MAPLE-deposited thin films were examined using Fourier transform infrared spectroscopy, atomic force microscopy, X-ray photoelectron spectroscopy, and contact-angle measurements. We have found that the main functional groups of the mussel-adhesive protein analog are present in the transferred film. These adhesive materials have several potential electronic, medical, and marine applications.

  19. Activated Leukocyte Cell Adhesion Molecule Expression and Shedding in Thyroid Tumors

    PubMed Central

    Miccichè, Francesca; Da Riva, Luca; Fabbi, Marina; Pilotti, Silvana; Mondellini, Piera; Ferrini, Silvano; Canevari, Silvana; Pierotti, Marco A.; Bongarzone, Italia

    2011-01-01

    Activated leukocyte cell adhesion molecule (ALCAM, CD166) is expressed in various tissues, cancers, and cancer-initiating cells. Alterations in expression of ALCAM have been reported in several human tumors, and cell adhesion functions have been proposed to explain its association with cancer. Here we documented high levels of ALCAM expression in human thyroid tumors and cell lines. Through proteomic characterization of ALCAM expression in the human papillary thyroid carcinoma cell line TPC-1, we identified the presence of a full-length membrane-associated isoform in cell lysate and of soluble ALCAM isoforms in conditioned medium. This finding is consistent with proteolytically shed ALCAM ectodomains. Nonspecific agents, such as phorbol myristate acetate (PMA) or ionomycin, provoked increased ectodomain shedding. Epidermal growth factor receptor stimulation also enhanced ALCAM secretion through an ADAM17/TACE-dependent pathway. ADAM17/TACE was expressed in the TPC-1 cell line, and ADAM17/TACE silencing by specific small interfering RNAs reduced ALCAM shedding. In addition, the CGS27023A inhibitor of ADAM17/TACE function reduced ALCAM release in a dose-dependent manner and inhibited cell migration in a wound-healing assay. We also provide evidence for the existence of novel O-glycosylated forms and of a novel 60-kDa soluble form of ALCAM, which is particularly abundant following cell stimulation by PMA. ALCAM expression in papillary and medullary thyroid cancer specimens and in the surrounding non-tumoral component was studied by western blot and immunohistochemistry, with results demonstrating that tumor cells overexpress ALCAM. These findings strongly suggest the possibility that ALCAM may have an important role in thyroid tumor biology. PMID:21364949

  20. Mechanical Activation of a Multimeric Adhesive Protein Through Domain Conformational Change

    NASA Astrophysics Data System (ADS)

    Wijeratne, Sithara S.; Botello, Eric; Yeh, Hui-Chun; Zhou, Zhou; Bergeron, Angela L.; Frey, Eric W.; Patel, Jay M.; Nolasco, Leticia; Turner, Nancy A.; Moake, Joel L.; Dong, Jing-fei; Kiang, Ching-Hwa

    2013-03-01

    The mechanical force-induced activation of the adhesive protein von Willebrand factor (VWF), which experiences high hydrodynamic forces, is essential in initiating platelet adhesion. The importance of the mechanical force-induced functional change is manifested in the multimeric VWF’s crucial role in blood coagulation, when high fluid shear stress activates plasma VWF (PVWF) multimers to bind platelets. Here, we showed that a pathological level of high shear stress exposure of PVWF multimers results in domain conformational changes, and the subsequent shifts in the unfolding force allow us to use force as a marker to track the dynamic states of the multimeric VWF. We found that shear-activated PVWF multimers are more resistant to mechanical unfolding than nonsheared PVWF multimers, as indicated in the higher peak unfolding force. These results provide insight into the mechanism of shear-induced activation of PVWF multimers.

  1. Selective inhibition by grape seed proanthocyanidin extracts of cell adhesion molecule expression induced by advanced glycation end products in endothelial cells.

    PubMed

    Zhang, Feng-Lei; Gao, Hai-Qing; Wu, Jian-Min; Ma, Ya-Bing; You, Bei-An; Li, Bao-Ying; Xuan, Jun-Hua

    2006-08-01

    The interaction of advanced glycation end products (AGE) with their cell surface receptors for AGEs (RAGE) has been causally implicated in the pathogenesis of diabetic vascular complications and has been shown to stimulate cell adhesion molecule expression in endothelial cells via induction of reactive oxygen species (ROS). Alternatively, grape seed proanthocyanidin extracts (GSPE), which are naturally occurring polyphenolic compounds, have been reported to possess potent radical scavenging and antioxidant properties and to display significant cardiovascular protective action. In this study, we investigated whether GSPE could inhibit AGE-induced cell adhesion molecule expression through interference with ROS generations in human umbilical vein endothelial cells. AGE-modified bovine serum albumin (AGE-BSA) was prepared by incubating BSA with a high concentration of glucose. Stimulation of cultured human umbilical vein endothelial cells with 200 microg/mL of AGE-BSA significantly enhanced intracellular ROS formation and subsequently upregulated the expression of vascular cell adhesion molecule-1 (VCAM) and intercellular adhesion molecule-1 (ICAM-1), whereas both unmodified BSA and GSPE alone were without effect. However, preincubation of different concentrations of GSPE markedly downregulated AGE-BSA-induced VCAM-1 expression at the surface protein and mRNA level in a concentration-dependent manner, but the increased ICAM-1 expression was not affected by GSPE treatment. Meanwhile, the inhibition by GSPE of intracellular ROS generation was also observed at defined time periods. These results demonstrate that GSPE can inhibit the enhanced VCAM-1 expression but not ICAM-1 in AGE-exposed endothelial cells by suppressing ROS generation. Hence, GSPE may have therapeutic potential in the prevention and treatment of vascular complications in patients with diabetes.

  2. Inhibitory effect of butein on tumor necrosis factor-α-induced expression of cell adhesion molecules in human lung epithelial cells via inhibition of reactive oxygen species generation, NF-κB activation and Akt phosphorylation.

    PubMed

    Jang, Ji Hoon; Yang, Eun Sun; Min, Kyoung-Jin; Kwon, Taeg Kyu

    2012-12-01

    Cell adhesion molecules play an important role in inflammatory response, angiogenesis and tumor progression. Butein (tetrahydroxychalcone) is a small molecule from natural sources, known to be a potential therapeutic drug with anti-inflammatory, anticancer and antioxidant activities. In the present study, we investigated the inhibitory effect of butein on tumor necrosis factor (TNF)-α-induced adhesion molecule expression and its molecular mechanism of action. Butein significantly decreased TNF-α-induced monocyte (U937) cell adhesion to lung epithelial cells in a dose-dependent manner. Butein also inhibited the protein and mRNA expression of intercellular cell adhesion molecule-1 (ICAM-1) and vascular cell adhesion molecule-1 (VCAM-1) in TNF-α-stimulated A549 human lung epithelial cells in a dose-dependent manner. Butein inhibited TNF-α-induced reactive oxygen species (ROS) generation and nuclear factor-κB (NF-κB) activation in A549 cells; it also inhibited the phosphorylation of MAPKs and Akt, suggesting that the MAPK/Akt signaling pathway may be involved in the butein-mediated inhibition of TNF-α-induced leukocyte adhesion to A549 cells. Collectively, our results suggest that butein affects cell adhesion through the inhibition of TNF-α-induced ICAM-1 and VCAM-1 expression by inhibiting the NF-κB/MAPK/Akt signaling pathway and ROS generation, thereby, elucidating the role of butein in the anti-inflammatory response.

  3. A small fibronectin-mimicking protein from bacteria induces cell spreading and focal adhesion formation.

    PubMed

    Tegtmeyer, Nicole; Hartig, Roland; Delahay, Robin M; Rohde, Manfred; Brandt, Sabine; Conradi, Jens; Takahashi, Seiichiro; Smolka, Adam J; Sewald, Norbert; Backert, Steffen

    2010-07-23

    Fibronectin, a 250-kDa eukaryotic extracellular matrix protein containing an RGD motif plays crucial roles in cell-cell communication, development, tissue homeostasis, and disease development. The highly complex fibrillar fibronectin meshwork orchestrates the functions of other extracellular matrix proteins, promoting cell adhesion, migration, and intracellular signaling. Here, we demonstrate that CagL, a 26-kDa protein of the gastric pathogen and type I carcinogen Helicobacter pylori, mimics fibronectin in various cellular functions. Like fibronectin, CagL contains a RGD motif and is located on the surface of the bacterial type IV secretion pili as previously shown. CagL binds to the integrin receptor alpha(5)beta(1) and mediates the injection of virulence factors into host target cells. We show that purified CagL alone can directly trigger intracellular signaling pathways upon contact with mammalian cells and can complement the spreading defect of fibronectin(-/-) knock-out cells in vitro. During interaction with various human and mouse cell lines, CagL mimics fibronectin in triggering cell spreading, focal adhesion formation, and activation of several tyrosine kinases in an RGD-dependent manner. Among the activated factors are the nonreceptor tyrosine kinases focal adhesion kinase and Src but also the epidermal growth factor receptor and epidermal growth factor receptor family member Her3/ErbB3. Interestingly, fibronectin activates a similar range of tyrosine kinases but not Her3/ErbB3. These findings suggest that the bacterial protein CagL not only exhibits functional mimicry with fibronectin but is also capable of activating fibronectin-independent signaling events. We thus postulate that CagL may contribute directly to H. pylori pathogenesis by promoting aberrant signaling cross-talk within host cells.

  4. Redox Capacity of an Extracellular Matrix Protein Associated with Adhesion in Mytilus californianus.

    PubMed

    Nicklisch, Sascha C T; Spahn, Jamie E; Zhou, Hongjun; Gruian, Cristina M; Waite, J Herbert

    2016-04-05

    Adhesive mussel foot proteins (Mfps) rely in part on DOPA (3,4-dihydroxyphenyl-l-alanine) side chains to mediate attachment to mineral surfaces underwater. Oxidation of DOPA to Dopaquinone (Q) effectively abolishes the adsorption of Mfps to these surfaces. The thiol-rich mussel foot protein-6 (Mfp-6) rescues adhesion compromised by adventitious DOPA oxidation by reducing Q back to DOPA. The redox chemistry and kinetics of foot-extracted Mfp-6 were investigated by using a nonspecific chromogenic probe to equilibrate with the redox pool. Foot-extracted Mfp-6 has a reducing capacity of ~17 e(-) per protein; half of this comes from the cysteine residues, whereas the other half comes from other constituents, probably a cohort of four or five nonadhesive, redox-active DOPA residues in Mfp-6 with an anodic peak potential ~500 mV lower than that for oxidation of cysteine to cystine. At higher pH, DOPA redox reversibility is lost possibly due to Q scavenging by Cys thiolates. Analysis by one- and two-dimensional proton nuclear magnetic resonance identified a pronounced β-sheet structure with a hydrophobic core in foot-extracted Mfp-6 protein. The structure endows redox-active side chains in Mfp-6, i.e., cysteine and DOPA, with significant reducing power over a broad pH range, and this power is measurably diminished in recombinant Mfp-6.

  5. Glutamate Receptor Interacting Protein 1 Mediates Platelet Adhesion and Thrombus Formation

    PubMed Central

    Modjeski, Kristina L.; Ture, Sara K.; Field, David J.; Cameron, Scott J.; Morrell, Craig N.

    2016-01-01

    Thrombosis-associated pathologies, such as myocardial infarction and stroke, are major causes of morbidity and mortality worldwide. Because platelets are necessary for hemostasis and thrombosis, platelet directed therapies must balance inhibiting platelet function with bleeding risk. Glutamate receptor interacting protein 1 (GRIP1) is a large scaffolding protein that localizes and organizes interacting proteins in other cells, such as neurons. We have investigated the role of GRIP1 in platelet function to determine its role as a molecular scaffold in thrombus formation. Platelet-specific GRIP1-/- mice were used to determine the role of GRIP1 in platelets. GRIP1-/- mice had normal platelet counts, but a prolonged bleeding time and delayed thrombus formation in a FeCl3-induced vessel injury model. In vitro stimulation of WT and GRIP1-/- platelets with multiple agonists showed no difference in platelet activation. However, in vivo platelet rolling velocity after endothelial stimulation was significantly greater in GRIP1-/- platelets compared to WT platelets, indicating a potential platelet adhesion defect. Mass spectrometry analysis of GRIP1 platelet immunoprecipitation revealed enrichment of GRIP1 binding to GPIb-IX complex proteins. Western blots confirmed the mass spectrometry findings that GRIP1 interacts with GPIbα, GPIbβ, and 14-3-3. Additionally, in resting GRIP1-/- platelets, GPIbα and 14-3-3 have increased interaction compared to WT platelets. GRIP1 interactions with the GPIb-IX binding complex are necessary for normal platelet adhesion to a stimulated endothelium. PMID:27631377

  6. Nanometric protein-patch arrays on glass and polydimethylsiloxane for cell adhesion studies.

    PubMed

    Pi, Fuwei; Dillard, Pierre; Limozin, Laurent; Charrier, Anne; Sengupta, Kheya

    2013-07-10

    We present a simple cost-effective benchtop protocol to functionalize glass and polydimethylsiloxane (PDMS) with nanometric protein patches for cell adhesion studies. Evaporation masks, covering macroscopic areas on glass, were made using improved strategies for self-assembly of colloidal microbeads which then served as templates for creating the protein patch arrays via the intermediate steps of organo-aminosilane deposition and polyethylene-glycol grafting. The diameter of the patches could be varied down to about 80 nm. The glass substrates were used for advanced optical imaging of T-lymphocytes to explore adhesion by reflection interference contrast microscopy and the possible colocalization of T-cell receptor microclusters and the activating protein patches by total internal reflection fluorescence microscopy. The selectively functionalized glass could also serve as template for transferring the protein nanopatches to the surface of a soft elastomer. We demonstrated successful reverse contact printing onto the surface of thin layers of PDMS with stiffness ranging from 30 KPa to 3 MPa.

  7. Expression of HLA-ABC, HLA-DR and intercellular adhesion molecule-1 in oesophageal carcinoma.

    PubMed Central

    Rockett, J C; Darnton, S J; Crocker, J; Matthews, H R; Morris, A G

    1995-01-01

    AIM--To examine the expression of HLA-ABC and HLA-DR major histocompatibility (MHC) antigens and intercellular adhesion molecule (ICAM)-1 in normal, inflamed, metaplastic, and neoplastic oesophageal tissue and in freshly disaggregated tumours. METHODS--Sequential sections of frozen tissue and cytospins of freshly disaggregated tumour were stained using the ABC peroxidase system and monoclonal antibodies specific for HLA-ABC, HLA-DR and ICAM-1. RESULTS--Normal oesophageal tissue showed positive staining for HLA-ABC in the basal layers of the oesophageal squamous epithelium and on the epithelial cells of the submucosal oesophageal glands. HLA-DR and ICAM-1 were not detected in either of these cell types. In 20 of 37 (54%) carcinomas HLA-ABC was expressed weakly, with heterogeneous expression in nine (24%). Two tumours showed strong expression of HLA-ABC, but 15 of 37 (41%) were negative. HLA-DR and ICAM-1 were expressed weakly in six of 37 (16%) carcinomas without correlation with each other or with the expression of HLA-ABC. CONCLUSIONS--HLA-ABC is absent from a high proportion of oesophageal carcinomas (41%) and is otherwise variably and weakly expressed with strong expression in only a small fraction (3%). In other carcinomas there is a higher level of HLA-ABC expression. This discrepancy may partly explain the aggressive nature of oesophageal carcinomas. HLA-DR and ICAM-1 are not normally expressed on those cells from which oesophageal carcinomas are thought to arise. The limited expression found here could suggest a partial or inhibited immune response against oesophageal carcinoma. In vivo repressive factors may be involved. Images PMID:7665697

  8. Neural cell adhesion molecule expression in dilated cardiomyopathy is associated with intramyocardial inflammation and hypertrophy.

    PubMed

    Ostermann, Karsten; Schultheiss, Heinz-Peter; Noutsias, Michel

    2017-03-18

    Chronic intramyocardial inflammation (inflammatory cardiomyopathy/DCMi) is linked to the pathogenesis of dilated cardiomyopathy (DCM). Neural cell adhesion molecule (NCAM) is involved in orchestrating cardiac muscle morphogenesis, but is down-regulated after embryogenesis. We investigated NCAM expression in adult DCM hearts, its possible association with DCMi-parameters, and with cardiomyocyte hypertrophy (CMH). Endomyocardial biopsies (EMBs) from DCM patients (n=85; n=37 females; age: 48±19years; LVEF <40%) and controls from non-cardiac deaths were immunostained for DCMi markers and for NCAM expression, and quantified by digital image analysis (DIA). NCAM expression on the intercalated discs and the sarcolemma was confirmed in n=46 (54%) of the DCM-EMBs. In the 17 controls, NCAM expression was confined to scattered intramyocardial nerves, but was absent on cardiomyocytes. DIA-quantified area fraction (AF) of NCAM was significantly (p=0.0001) higher in the DCM hearts (0.0044±0.017) compared with the controls (0.0006±0.0004). Multivariate analysis of DIA-quantified NCAM-AF revealed significant associations with infiltrates (CD18(+), CD11a/LFA-1(+), CD11b/Mac-1(+), TNFα(+), CD3(+)) and with endothelial cell adhesion molecules (CAM; CD54/ICAM-1 and CD29; p<0.05). The mean cardiomyocyte diameter (MCD) correlated highly significantly (p<0.01) with NCAM-AF, ICAM-1-AF, CD29-AF, CD18(+) and TNFa(+) infiltrates, and was associated less significantly (p<0.05) with CD3(+), CD11a/LFA-1(+), and CD11b/Mac-1(+) infiltrates. In conclusion, NCAM-expression in ca. 50% of adult DCM hearts is associated with CMH, and may be induced by inflammatory pathways.

  9. Organization of pp60src and selected cytoskeletal proteins within adhesion plaques and junctions of Rous sarcoma virus-transformed rat cells

    PubMed Central

    1981-01-01

    The localization of pp60src within adhesion structures of epithelioid rat kidney cells transformed by the Schmidt-Ruppin strain of Rous sarcoma virus was compared to the organization of actin, alpha-actinin, vinculin (a 130,000-dalton protein), tubulin, and the 58,000-dalton intermediate filament protein. The adhesion structures included both adhesion plaques and previously uncharacterized adhesive regions formed at cell-cell junctions. We have termed these latter structures "adhesion junctions." Both adhesion plaques and adhesion junctions were identified by interference-reflection microscopy and compared to the location of pp60src and the various cytoskeletal proteins by double fluorescence. The results demonstrated that the src gene product was found within both adhesion plaques and the adhesion junctions. In addition, actin, alpha-actinin, and vinculin were also localized within the same pp60src-containing adhesion structures. In contrast, tubulin and the 58,000-dalton intermediate filament protein were not associated with either adhesion plaques or adhesion junctions. Both adhesion plaques and adhesion junctions were isolated as substratum-bound structures and characterized by scanning electron microscopy. Immunofluorescence revealed that pp60src, actin, alpha-actinin, and vinculin were organized within specific regions of the adhesion junctions. Heavy accumulations of actin and alpha-actinin were found on both sides of the junctions with a narrow gap of unstained material at the midline, whereas pp60src stain was more intense in this central region. Antibody to vinculin stained double narrow lines defining the periphery of the junctional complexes but was excluded from the intervening region. In addition, the distribution of vinculin relative to pp60src within adhesion plaques suggested an inverse relationship between the presence of these two proteins. Overall, these results establish a close link between the src gene product and components of the

  10. Dependence of corneal keratocyte adhesion, spreading, and integrin β1 expression on deacetylated chitosan coating.

    PubMed

    Sun, Chi-Chin; Chou, Shih-Feng; Lai, Jui-Yang; Cho, Ching-Hsien; Lee, Chih-Hung

    2016-06-01

    This study reports, for the first time, the regulation of corneal keratocyte adhesion, spreading, morphology, and integrin gene expression on chitosan coating due to the effects of deacetylation. The degree of deacetylation (DD) in chitosan materials was confirmed by elemental analysis, gel permeation chromatography, and Fourier transform infrared spectroscopy. In this study, chitosan samples with the same molecular weight level but varying DD (74.1 ± 0.5%, 84.4 ± 0.7%, and 94.2 ± 0.5%) were obtained by heat-alkaline treatment under a nitrogen atmosphere. For higher DD groups, the biopolymer carried abundant amino groups since the deacetylation process removed larger amount of acetyl groups from the chitosan molecules. Results showed that the mechanical stability and crystallinity of the chitosan coatings significantly increased with increasing DD value. Fibronectin adsorption, keratocyte adhesion, and cell spreading exhibited a positive correlation with DD due to the chemical functionality of polysaccharides (bearing acetyl and amino groups) and increase of substrate stiffness and crystallinity. In particular, when adhered to chitosan coatings with a DD value of 74.1%, the keratocytes appeared to be fibroblastic, elongated, and spindle shape, indicating a loss of their characteristic dendritic morphology. Furthermore, the gene expression of integrin β1 (i.e., a cell-matrix adhesion molecule) was significantly up-regulated on the chitosan coatings with higher DD, which supports favorable attachment of corneal keratocytes. Our findings suggest that DD-mediated physicochemical properties of chitosan coatings greatly affect cell-substrate crosstalk during corneal keratocyte cultivation.

  11. High-Frequency Mechanostimulation of Cell Adhesion.

    PubMed

    Kadem, Laith F; Suana, K Grace; Holz, Michelle; Wang, Wei; Westerhaus, Hannes; Herges, Rainer; Selhuber-Unkel, Christine

    2017-01-02

    Cell adhesion is regulated by molecularly defined protein interactions and by mechanical forces, which can activate a dynamic restructuring of adhesion sites. Previous attempts to explore the response of cell adhesion to forces have been limited to applying mechanical stimuli that involve the cytoskeleton. In contrast, we here apply a new, oscillatory type of stimulus through push-pull azobenzenes. Push-pull azobenzenes perform a high-frequency, molecular oscillation upon irradiation with visible light that has frequently been applied in polymer surface relief grating. We here use these oscillations to address single adhesion receptors. The effect of molecular oscillatory forces on cell adhesion has been analyzed using single-cell force spectroscopy and gene expression studies. Our experiments demonstrate a reinforcement of cell adhesion as well as upregulated expression levels of adhesion-associated genes as a result of the nanoscale "tickling" of integrins. This novel type of mechanical stimulus provides a previously unprecedented molecular control of cellular mechanosensing.

  12. Expression of cell adhesion molecules and doublecortin in canine anaplastic meningiomas.

    PubMed

    Ide, T; Uchida, K; Suzuki, K; Kagawa, Y; Nakayama, H

    2011-01-01

    Tumor cell invasion into the surrounding nervous tissue is one of the histologic hallmarks of anaplastic meningiomas. To identify other possible markers for aggression in canine meningiomas, the relationship between histologic features and the expression of molecules involved in cell adhesion, cell proliferation, and invasion was examined. Immunohistochemistry for epithelial cadherin (E-cadherin), neural cadherin (N-cadherin), β-catenin, doublecortin (DCX), and Ki-67 was performed for 55 cases of canine meningioma. DCX was preferentially expressed in tumor cells invading the brain parenchyma (12 of 14 cases), suggesting its involvement in the invasion process. Regardless of the histologic type, E-cadherin and N-cadherin expression was observed in 31 of 55 and 44 of 55 cases, respectively. There was a significant positive correlation between DCX and N-cadherin expression and a significant negative correlation between E-cadherin and N-cadherin expression, suggesting that decreased E-cadherin and increased N-cadherin expression induce DCX expression. Typical membranous β-catenin expression was observed in 10 of 55 cases, whereas nuclear translocation was observed in 33 cases. Nuclear β-catenin expression was frequently found in anaplastic meningiomas (12 of 14 cases). The Ki-67 labeling indices were significantly higher in anaplastic meningiomas than in other types. These findings indicate that the expression of N-cadherin and DCX and the nuclear translocation of β-catenin are closely associated with the presence of invasion and anaplasia in canine meningiomas. Notably, granular cell meningiomas were negative for almost all the molecules examined, suggesting that they have a different tumor biology than other meningiomas.

  13. Effect of Cell Adhesion Molecule 1 Expression on Intracellular Granule Movement in Pancreatic α Cells.

    PubMed

    Yokawa, Satoru; Furuno, Tadahide; Suzuki, Takahiro; Inoh, Yoshikazu; Suzuki, Ryo; Hirashima, Naohide

    2016-09-01

    Although glucagon secreted from pancreatic α cells plays a role in increasing glucose concentrations in serum, the mechanism regulating glucagon secretion from α cells remains unclear. Cell adhesion molecule 1 (CADM1), identified as an adhesion molecule in α cells, has been reported not only to communicate among α cells and between nerve fibers, but also to prevent excessive glucagon secretion from α cells. Here, we investigated the effect of CADM1 expression on the movement of intracellular secretory granules in α cells because the granule transport is an important step in secretion. Spinning disk microscopic analysis showed that granules moved at a mean velocity of 0.236 ± 0.010 μm/s in the mouse α cell line αTC6 that expressed CADM1 endogenously. The mean velocity was significantly decreased in CADM1-knockdown (KD) cells (mean velocity: 0.190 ± 0.016 μm/s). The velocity of granule movement decreased greatly in αTC6 cells treated with the microtubule-depolymerizing reagent nocodazole, but not in αTC6 cells treated with the actin-depolymerizing reagent cytochalasin D. No difference in the mean velocity was observed between αTC6 and CADM1-KD cells treated with nocodazole. These results suggest that intracellular granules in pancreatic α cells move along the microtubule network, and that CADM1 influences their velocity.

  14. Adhesion of Type 1-Fimbriated Escherichia coli to Abiotic Surfaces Leads to Altered Composition of Outer Membrane Proteins

    PubMed Central

    Otto, Karen; Norbeck, Joakim; Larsson, Thomas; Karlsson, Karl-Anders; Hermansson, Malte

    2001-01-01

    Phenotypic differences between planktonic bacteria and those attached to abiotic surfaces exist, but the mechanisms involved in the adhesion response of bacteria are not well understood. By the use of two-dimensional (2D) polyacrylamide gel electrophoresis, we have demonstrated that attachment of Escherichia coli to abiotic surfaces leads to alteration in the composition of outer membrane proteins. A major decrease in the abundance of resolved proteins was observed during adhesion of type 1-fimbriated E. coli strains, which was at least partly caused by proteolysis. Moreover, a study of fimbriated and nonfimbriated mutants revealed that these changes were due mainly to type 1 fimbria-mediated surface contact and that only a few changes occurred in the outer membranes of nonfimbriated mutant strains. Protein synthesis and proteolytic degradation were involved to different extents in adhesion of fimbriated and nonfimbriated cells. While protein synthesis appeared to affect adhesion of only the nonfimbriated strain, proteolytic activity mostly seemed to contribute to adhesion of the fimbriated strain. Using matrix-assisted laser desorption ionization–time of flight mass spectrometry, six of the proteins resolved by 2D analysis were identified as BtuB, EF-Tu, OmpA, OmpX, Slp, and TolC. While the first two proteins were unaffected by adhesion, the levels of the last four were moderately to strongly reduced. Based on the present results, it may be suggested that physical interactions between type 1 fimbriae and the surface are part of a surface-sensing mechanism in which protein turnover may contribute to the observed change in composition of outer membrane proteins. This change alters the surface characteristics of the cell envelope and may thus influence adhesion. PMID:11274103

  15. Taking Orders from Light: Photo-Switchable Working/Inactive Smart Surfaces for Protein and Cell Adhesion.

    PubMed

    Zhang, Junji; Ma, Wenjing; He, Xiao-Peng; Tian, He

    2017-03-15

    Photoresponsive smart surfaces are promising candidates for a variety of applications in optoelectronics and sensing devices. The use of light as an order signal provides advantages of remote and noninvasive control with high temporal and spatial resolutions. Modification of the photoswitches with target biomacromolecules, such as peptides, DNA, and small molecules including folic acid derivatives and sugars, has recently become a popular strategy to empower the smart surfaces with an improved detection efficiency and specificity. Herein, we report the construction of photoswitchable self-assembled monolayers (SAMs) based on sugar (galactose/mannose)-decorated azobenzene derivatives and determine their photoswitchable, selective protein/cell adhesion performances via electrochemistry. Under alternate UV/vis irradiation, interconvertible high/low recognition and binding affinity toward selective lectins (proteins that recognize sugars) and cells that highly express sugar receptors are achieved. Furthermore, the cis-SAMs with a low binding affinity toward selective proteins and cells also exhibit minimal response toward unselective protein and cell samples, which offers the possibility in avoiding unwanted contamination and consumption of probes prior to functioning for practical applications. Besides, the electrochemical technique used facilitates the development of portable devices based on the smart surfaces for on-demand disease diagnosis.

  16. Gene expression analysis of tuberous sclerosis complex cortical tubers reveals increased expression of adhesion and inflammatory factors

    PubMed Central

    Boer, Karin; Crino, Peter B.; Gorter, Jan A.; Nellist, Mark; Jansen, Floor E.; Spliet, Wim G.M.; van Rijen, Peter C.; Wittink, Floyd R.A.; Breit, Timo M.; Troost, Dirk; Wadman, Wytse J.; Aronica, Eleonora

    2009-01-01

    Cortical tubers in patients with tuberous sclerosis complex are associated with disabling neurological manifestations, including intractable epilepsy. While these malformations are believed to result from the effects of TSC1 or TSC2 gene mutations, the molecular mechanisms leading to tuber formation, as well as the onset of seizures remain largely unknown. We used the Affymetrix Gene Chip platform to provide the first genome wide investigation of gene expression in surgically resected tubers, compared with histological normal perituberal tissue from the same patients or autopsy control tissue. We identified 2501 differentially expressed genes in cortical tubers compared with autopsy controls. Expression of genes associated with cell adhesion e.g., VCAM1, integrins and CD44, or with the inflammatory response, including complement factors, serpinA3, CCL2 and several cytokines, was increased in cortical tubers, whereas genes related to synaptic transmission e.g., the glial glutamate transporter GLT-1, and voltage-gated channel activity, exhibited lower expression. Gene expression in perituberal cortex was distinct from autopsy control cortex suggesting that even in the absence of tissue pathology the transcriptome is altered in TSC. Changes in gene expression yield insights into new candidate genes that may contribute to tuber formation or seizure onset, representing new targets for potential therapeutic development. PMID:19912235

  17. Transfected HEK293 Cells Expressing Functional Recombinant Intercellular Adhesion Molecule 1 (ICAM-1) – A Receptor Associated with Severe Plasmodium falciparum Malaria

    PubMed Central

    Bengtsson, Anja; Joergensen, Louise; Barbati, Zachary R.; Craig, Alister; Hviid, Lars; Jensen, Anja T. R.

    2013-01-01

    Intercellular adhesion molecule 1 (ICAM-1) is a membrane-bound glycoprotein expressed on endothelial cells and cells of the immune system. Human ICAM-1 mediates adhesion and migration of leucocytes, and is implicated in inflammatory pathologies, autoimmune diseases and in many cancer processes. Additionally, ICAM-1 acts as receptor for pathogens like human rhinovirus and Plasmodium falciparum malaria parasites. A group of related P. falciparum erythrocyte membrane protein 1 (PfEMP1) domains, the DBLβ, mediates ICAM-1 binding of P. falciparum-infected erythrocytes. This ICAM‑1-binding phenotype has been suggested to be involved in the development of cerebral malaria. However, more studies identifying cross-reactive antibody and ICAM-1-binding epitopes and the establishment of a clinical link between DBLβ expression and e.g. cerebral malaria are needed before the DBLβ domains can be put forward as vaccine candidates and go into clinical trials. Such studies require availability of functional recombinant ICAM-1 in large quantities. In this study, we compared recombinant ICAM-1 expressed in HEK293 and COS-7 cells with mouse myeloma NS0 ICAM-1 purchased from a commercial vendor in terms of protein purity, yield, fold, ability to bind DBLβ, and relative cost. We present a HEK293 cell-based, high-yield expression and purification scheme for producing inexpensive, functional ICAM‑1. ICAM-1 expressed in HEK293 is applicable to malaria research and can also be useful in other research fields. PMID:23936131

  18. Cannabinoids modulate Olig2 and polysialylated neural cell adhesion molecule expression in the subventricular zone of post-natal rats through cannabinoid receptor 1 and cannabinoid receptor 2.

    PubMed

    Arévalo-Martín, Angel; García-Ovejero, Daniel; Rubio-Araiz, Ana; Gómez, Oscar; Molina-Holgado, Francisco; Molina-Holgado, Eduardo

    2007-09-01

    The subventricular zone (SVZ) is a source of post-natal glial precursors that can migrate to the overlying white matter, where they may differentiate into oligodendrocytes. We showed that, in the post-natal SVZ ependymocytes, radial glia and astrocyte-like cells express cannabinoid receptor 1 (CB1), whereas cannabinoid receptor 2 (CB2) is found in cells expressing the polysialylated neural cell adhesion molecule. To study CB1 and CB2 function, post-natal rats were exposed to selective CB1 or CB2 agonists (arachidonyl-2-chloroethylamide and JWH-056, respectively) for 15 days. Accordingly, we found that CB1 activation increases the number of Olig2-positive cells in the dorsolateral SVZ, whereas CB2 activation increases polysialylated neural cell adhesion molecule expression in this region. As intense myelination occurs during the first weeks of post-natal development, we examined how modulating these factors affected the expression of myelin basic protein. Pharmacological administration of agonists and antagonists of CB1 and CB2 showed that the activation of both receptors is needed to augment the expression of myelin basic protein in the subcortical white matter.

  19. Protein N-glycosylation in oral cancer: dysregulated cellular networks among DPAGT1, E-cadherin adhesion and canonical Wnt signaling.

    PubMed

    Varelas, Xaralabos; Bouchie, Meghan P; Kukuruzinska, Maria A

    2014-07-01

    N-Linked glycosylation (N-glycosylation) of proteins has long been associated with oncogenesis, but not until recently have the molecular mechanisms underlying this relationship begun to be unraveled. Here, we review studies describing how dysregulation of the N-glycosylation-regulating gene, DPAGT1, drives oral cancer. DPAGT1 encodes the first and rate-limiting enzyme in the assembly of the lipid-linked oligosaccharide precursor in the endoplasmic reticulum and thus mediates N-glycosylation of many cancer-related proteins. DPAGT1 controls N-glycosylation of E-cadherin, the major epithelial cell-cell adhesion receptor and a tumor suppressor, thereby affecting intercellular adhesion and cytoskeletal dynamics. DPAGT1 also regulates and is regulated by Wnt/β-catenin signaling, impacting the balance between proliferation and adhesion in homeostatic tissues. Thus, aberrant induction of DPAGT1 promotes a positive feedback network with Wnt/β-catenin that represses E-cadherin-based adhesion and drives tumorigenic phenotypes. Further, modification of receptor tyrosine kinases (RTKs) with N-glycans is known to control their surface presentation via the galectin lattice, and thus increased DPAGT1 expression likely contributes to abnormal activation of RTKs in oral cancer. Collectively, these studies suggest that dysregulation of the DPAGT1/Wnt/E-cadherin network underlies the etiology and pathogenesis of oral cancer.

  20. Measurement of adhesive forces between bacteria and protein-coated surfaces using optical tweezers

    NASA Astrophysics Data System (ADS)

    Simpson, Kathryn H.; Bowden, Gabriela; Hook, Magnus; Anvari, Bahman

    2002-05-01

    Bacterial adhesion is a primary cause of failure in implanted medical devices. Bacteria commonly found in device-related infections, such as S. aureus, have multiple cell surface adhesins which mediate specific adhesion to molecules found in extracellular matrix and blood plasma. Adhesins recognizing fibrinogen, fibronectin, collagen, and elastin molecules have been isolated in S. aureus. We have used optical tweezers to measure the adhesive force between a single bacterium and a protein-coated surface. Various concentrations of fibronectin, fibrinogen, or whole plasma were immobilized onto 10-micrometers diameter polystyrene microspheres. We optically trapped a bacterium with a titanium-sapphire laser tuned to 830 nm and contacted the cell with a coated bead. We determined the minimum force necessary to separate the cell and bead. For beads coated with fibronectin and fibrinogen, detachment force values occurred as approximate integer multiples of an estimated single bond detachment force. With plasma-coated beads, only cells lacking the fibrinogen adhesin could be detached; therefore, we believe that either this adhesin is prevalent on wilde-type cells, or it is preferentially adsorbed onto the beads. Additionally, the whole plasma detachment forces appeared random; therefore, we believe that many adhesins participate in boding to plasma.

  1. Influence of preadsorbed milk proteins on adhesion of Listeria monocytogenes to hydrophobic and hydrophilic silica surfaces.

    PubMed Central

    al-Makhlafi, H; McGuire, J; Daeschel, M

    1994-01-01

    The adsorption of beta-lactoglobulin, bovine serum albumin, alpha-lactalbumin, and beta-casein for 8 h and beta-lactoglobulin and bovine serum albumin for 1 h at silanized silica surfaces of low and high hydrophobicity, followed by incubation in buffer and contact with Listeria monocytogenes, resulted in different numbers of cells adhered per unit of surface area. Adhesion to both surfaces was greatest when beta-lactoglobulin was present and was lowest when bovine serum albumin was present. Preadsorption of alpha-lactalbumin and beta-casein showed an intermediate effect on cell adhesion. Adsorption of beta-lactoglobulin for 1 h resulted in a generally lower number of cells adhered compared with the 8-h adsorption time, while the opposite result was observed with respect to bovine serum albumin. The adhesion data were explainable in terms of the relative rates of arrival to the surface and postadsorptive conformational change among the proteins, in addition to the extent of surface coverage in each case. PMID:7986033

  2. Nanometer polymer surface features: the influence on surface energy, protein adsorption and endothelial cell adhesion

    NASA Astrophysics Data System (ADS)

    Carpenter, Joseph; Khang, Dongwoo; Webster, Thomas J.

    2008-12-01

    Current small diameter (<5 mm) synthetic vascular graft materials exhibit poor long-term patency due to thrombosis and intimal hyperplasia. Tissue engineered solutions have yielded functional vascular tissue, but some require an eight-week in vitro culture period prior to implantation—too long for immediate clinical bedside applications. Previous in vitro studies have shown that nanostructured poly(lactic-co-glycolic acid) (PLGA) surfaces elevated endothelial cell adhesion, proliferation, and extracellular matrix synthesis when compared to nanosmooth surfaces. Nonetheless, these studies failed to address the importance of lateral and vertical surface feature dimensionality coupled with surface free energy; nor did such studies elicit an optimum specific surface feature size for promoting endothelial cell adhesion. In this study, a series of highly ordered nanometer to submicron structured PLGA surfaces of identical chemistry were created using a technique employing polystyrene nanobeads and poly(dimethylsiloxane) (PDMS) molds. Results demonstrated increased endothelial cell adhesion on PLGA surfaces with vertical surface features of size less than 18.87 nm but greater than 0 nm due to increased surface energy and subsequently protein (fibronectin and collagen type IV) adsorption. Furthermore, this study provided evidence that the vertical dimension of nanometer surface features, rather than the lateral dimension, is largely responsible for these increases. In this manner, this study provides key design parameters that may promote vascular graft efficacy.

  3. Serum protein layers on parylene-C and silicon oxide: effect on cell adhesion.

    PubMed

    Delivopoulos, Evangelos; Ouberai, Myriam M; Coffey, Paul D; Swann, Marcus J; Shakesheff, Kevin M; Welland, Mark E

    2015-02-01

    Among the range of materials used in bioengineering, parylene-C has been used in combination with silicon oxide and in presence of the serum proteins, in cell patterning. However, the structural properties of adsorbed serum proteins on these substrates still remain elusive. In this study, we use an optical biosensing technique to decipher the properties of fibronectin (Fn) and serum albumin adsorbed on parylene-C and silicon oxide substrates. Our results show the formation of layers with distinct structural and adhesive properties. Thin, dense layers are formed on parylene-C, whereas thicker, more diffuse layers are formed on silicon oxide. These results suggest that Fn acquires a compact structure on parylene-C and a more extended structure on silicon oxide. Nonetheless, parylene-C and silicon oxide substrates coated with Fn host cell populations that exhibit focal adhesion complexes and good cell attachment. Albumin adopts a deformed structure on parylene-C and a globular structure on silicon oxide, and does not support significant cell attachment on either surface. Interestingly, the co-incubation of Fn and albumin at the ratio found in serum, results in the preferential adsorption of albumin on parylene-C and Fn on silicon oxide. This finding is supported by the exclusive formation of focal adhesion complexes in differentiated mouse embryonic stem cells (CGR8), cultured on Fn/albumin coated silicon oxide, but not on parylene-C. The detailed information provided in this study on the distinct properties of layers of serum proteins on substrates such as parylene-C and silicon oxide is highly significant in developing methods for cell patterning.

  4. Platelet adhesion and plasma protein adsorption control of collagen surfaces by He + ion implantation

    NASA Astrophysics Data System (ADS)

    Kurotobi, K.; Suzuki, Y.; Nakajima, H.; Suzuki, H.; Iwaki, M.

    2003-05-01

    He + ion implanted collagen-coated tubes with a fluence of 1 × 10 14 ions/cm 2 were exhibited antithrombogenicity. To investigate the mechanisms of antithrombogenicity of these samples, plasma protein adsorption assay and platelet adhesion experiments were performed. The adsorption of fibrinogen (Fg) and von Willebrand factor (vWf) was minimum on the He + ion implanted collagen with a fluence of 1 × 10 14 ions/cm 2. Platelet adhesion (using platelet rich plasma) was inhibited on the He + ion implanted collagen with a fluence of 1 × 10 14 ions/cm 2 and was accelerated on the untreated collagen and ion implanted collagen with fluences of 1 × 10 13, 1 × 10 15 and 1 × 10 16 ions/cm 2. Platelet activation with washed platelets was observed on untreated collagen and He + ion implanted collagen with a fluence of 1 × 10 14 ions/cm 2 and was inhibited with fluences of 1 × 10 13, 1 × 10 15 and 1 × 10 16 ions/cm 2. Generally, platelets can react with a specific ligand inside the collagen (GFOGER sequence). The results of platelets adhesion experiments using washed platelets indicated that there were no ligands such as GFOGER on the He + ion implanted collagen over a fluence of 1 × 10 13 ions/cm 2. On the 1 × 10 14 ions/cm 2 implanted collagen, no platelet activation was observed due to the influence of plasma proteins. From the above, it is concluded that the decrease of adsorbed Fg and vWf caused the antithrombogenicity of He + ion implanted collagen with a fluence of 1 × 10 14 ions/cm 2 and that plasma protein adsorption took an important role repairing the graft surface.

  5. A Novel Domain Cassette Identifies Plasmodium falciparum PfEMP1 Proteins Binding ICAM-1 and Is a Target of Cross-Reactive, Adhesion-Inhibitory Antibodies

    PubMed Central

    Bengtsson, Anja; Joergensen, Louise; Rask, Thomas S.; Olsen, Rebecca W.; Andersen, Marianne A.; Turner, Louise; Theander, Thor G.; Higgins, Matthew K.; Craig, Alister; Brown, Alan

    2013-01-01

    Cerebral Plasmodium falciparum malaria is characterized by adhesion of infected erythrocytes (IEs) to the cerebral microvasculature. This has been linked to parasites expressing the structurally related group A subset of the P. falciparum erythrocyte membrane protein 1 (PfEMP1) family of IE adhesion ligands and to IEs with affinity for ICAM-1. However, recent evidence has cast doubt on both these associations, tempering hopes of the feasibility of developing a vaccine based on ICAM-1–binding PfEMP1. In this study, we report the identification of a domain cassette (DC) present in group A var genes from six genetically distinct P. falciparum parasites. The three domains in the cassette, which we call DC4, had a high level of sequence identity and cluster together phylogenetically. Erythrocytes infected by these parasites and selected in vitro for expression of DC4 adhered specifically to ICAM-1. The ICAM-1–binding capacity of DC4 was mapped to the C-terminal third of its Duffy-binding–like β3 domain. DC4 was the target of broadly cross-reactive and adhesion-inhibitory IgG Abs, and levels of DC4-specific and adhesion-inhibitory IgG increased with age among P. falciparum–exposed children. Our study challenges earlier conclusions that group A PfEMP1 proteins are not central to ICAM-1–specific IE adhesion and support the feasibility of developing a vaccine preventing cerebral malaria by inhibiting cerebral IE sequestration. PMID:23209327

  6. Sticky Situation: An Investigation of Robust Aqueous-Based Recombinant Spider Silk Protein Coatings and Adhesives.

    PubMed

    Harris, Thomas I; Gaztambide, Danielle A; Day, Breton A; Brock, Cameron L; Ruben, Ashley L; Jones, Justin A; Lewis, Randolph V

    2016-11-14

    The mechanical properties and biocompatibility of spider silks have made them one of the most sought after and studied natural biomaterials. A biomimetic process has been developed that uses water to solvate purified recombinant spider silk proteins (rSSps) prior to material formation. The absence of harsh organic solvents increases cost effectiveness, safety, and decreases the environmental impact of these materials. This development allows for the investigation of aqueous-based rSSps as coatings and adhesives and their potential applications. In these studies it was determined that fiber-based rSSps in nonfiber formations have the capability to coat and adhere numerous substrates, whether rough, smooth, hydrophobic, or hydrophilic. Further, these materials can be functionalized for a variety of processes. Drug-eluting coatings have been made with the capacity to release a variety of compounds in addition to their inherent ability to prevent blood clotting and biofouling. Additionally, spider silk protein adhesives are strong enough to outperform some conventional glues and still display favorable tissue implantation properties. The physical properties, corresponding capabilities, and potential applications of these nonfibrous materials were characterized in this study. Mechanical properties, ease of manufacturing, biodegradability, biocompatibility, and functionality are the hallmarks of these revolutionary spider silk protein materials.

  7. Adhesion of Candida albicans to various dental implant surfaces and the influence of salivary pellicle proteins.

    PubMed

    Bürgers, Ralf; Hahnel, Sebastian; Reichert, Torsten E; Rosentritt, Martin; Behr, Michael; Gerlach, Till; Handel, Gerhard; Gosau, Martin

    2010-06-01

    Dental implants may be considered a potential reservoir for (re)infection with oral Candida albicans. Our aim was to evaluate initial fungal adhesion to three differentially textured titanium and one zirconia implant surface, and to correlate these findings to differences in specific surface characteristics (surface roughness (R(a)) and surface free energy (SFE)). Additionally, we investigated the influence of salivary protein films and two pellicle proteins (mucin and albumin). Implant surfaces were characterized by perthometer (R(a)) and goniometer (SFE) measurements. Implant specimens were rinsed with human whole saliva, mucin, albumin, or phosphate buffered saline and incubated in C. albicans suspension for 2.5h. Adherent fungi were quantified by means of a bioluminometric assay. The lowest amount of fungal cells was found on sand-blasted titanium, whereas zirconia implants did not show any reduced potential to adhere C. albicans. The influence of the implant SFE on fungal biofilm formation appears to be more important than the influence of R(a). The protein mucin enhanced C. albicans accumulation. In contrast, albumin is unlikely to be involved in the adhesion process of C. albicans.

  8. The effect of surface microtopography of poly(dimethylsiloxane) on protein adsorption, platelet and cell adhesion.

    PubMed

    Chen, Hong; Song, Wei; Zhou, Feng; Wu, Zhongkui; Huang, He; Zhang, Junhu; Lin, Quan; Yang, Bai

    2009-07-01

    Chemical homogeneous poly(dimethylsiloxane) (PDMS) surface with dot-like protrusion pattern was used to investigate the individual effect of surface microtopography on protein adsorption and subsequent biological responses. Fibrinogen (Fg) and fibronectin (Fn) were chosen as model proteins due to their effect on platelet and cell adhesion, respectively. Fg labeled with (125)I and fluorescein isothiocyanate (FITC) was used to study its adsorption on flat and patterned surfaces. Patterned surface has a 46% increase in the adsorption of Fg when compared with flat surface. However, the surface area of the patterned surface was only 8% larger than that of the flat surface. Therefore, the increase in the surface area was not the only factor responsible for the increase in protein adsorption. Clear fluorescent pattern was visualized on patterned surface, indicating that adsorbed Fg regularly distributed and adsorbed most on the flanks and valleys of the protrusions. Such distribution and local enrichment of Fg presumably caused the specific location of platelets adhered from platelet-rich plasma (PRP) and flowing whole blood (FWB) on patterned surface. Furthermore, the different combination of surface topography and pre-adsorbed Fn could influence the adhesion of L929 cells. The flat surface with pre-adsorbed Fn was the optimum substrate while the virgin patterned surface was the poor substrate in terms of L929 cells spread.

  9. The effects of cell adhesion on the growth and protein productivity of animal cells.

    PubMed

    Nishijima, K; Fujiki, T; Kojima, H; Iijima, S

    2000-07-01

    We investigated the effect of cell adhesion on cellgrowth and productivity of recombinant protein inChinese hamster ovary (CHO) cells. Cells cultured innormal tissue culture dishes attached to the dishsurfaces and grew as a monolayer, while cells culturedin non-treated dishes proliferated in suspension assingle cells without adhering to the dish surfaces. On an agarose-coated dish surface, cell aggregatesformed without attaching to the dish. Growth rates inboth suspension cultures were slightly lower thanthose in monolayer culture. Cell cycle analysisindicated that the duration of the G(1) phase insuspension cultures was longer than that in monolayerculture, suggesting that attachment to the substratummainly affected the transition from the G(1) to theS phase. Consistent with this, CDK inhibitor p27,that inhibits the G(1)S transition, was induced inthe cells cultured in suspension.To assess the productivity of recombinant proteins,CHO cells were transfected with a plasmid containingmurine interferon gamma (mIFN-gamma) under thecontrol of the cytomegalovirus promoter. Insuspension culture, mIFN-gamma productivity wasslightly lower than that in the monolayer culture. When protein kinase C was activated by phorbol ester,mIFN-gamma production was enhanced in both themonolayer and suspension cultures. However, theproductivity in the suspension culture was lower thanthat in the adherent culture even in the presence ofhigh concentrations of phorbol ester. These resultssuggested that cell adhesion to the substratum affectsvarious features of CHO cells.

  10. Quantum dots as bio-labels for the localization of a small plant adhesion protein

    NASA Astrophysics Data System (ADS)

    Ravindran, Sathyajith; Kim, Sunran; Martin, Rebecca; Lord, Elizabeth M.; Ozkan, Cengiz S.

    2005-01-01

    Recently, semiconducting nanoparticles have been successfully applied in live mammalian cell cultures, as alternative biological labels for multicolour imaging, by verifying known physiological processes. Here, we report the application of semiconducting nanoparticles to live plant cells in culture. Utilizing this technique, we have uncovered new knowledge regarding the localization of a plant pollen tube adhesion protein, stigma/stylar cysteine-rich adhesin (SCA). The potential of these nanoparticles is evident when the results were compared with conventional immunolocalization methods using fluorescently labelled antibodies.

  11. Green tea polyphenol epigallocatechin-3-gallate attenuates TNF-α-induced intercellular adhesion molecule-1 expression and monocyte adhesion to retinal pigment epithelial cells.

    PubMed

    Thichanpiang, Peeradech; Wongprasert, Kanokpan

    2015-01-01

    Epigallocatechin-3-gallate (EGCG) is a major polyphenol component of green tea (Camellia sinensis) and demonstrates anti-oxidant, anticancer and anti-inflammatory properties. EGCG has been shown to protect retinal pigment epithelium (RPE) against oxidative stress-induced cell death. The pathogenesis of diseases in the retina is usually initiated by local inflammation at the RPE cell layer, and inflammation is mostly associated with leukocyte migration and the secretion of pro-inflammatory cytokines. Whether EGCG can modulate the cytokine-induced inflammatory response of RPE, particularly leukocyte migration, has not been clearly elucidated, and was therefore the objective of this study. ARPE-19 cells were cultured with different concentrations of TNF-α in the presence or absence of EGCG to different time points. Intracellular reactive oxygen species (ROS) levels were determined. Intercellular adhesion molecule (ICAM)-1 and phosphor-NF-κB and IκB expression were determined by Western blot analysis. Phosphor-NF-κB nuclear translocation and monocyte-RPE adhesion were investigated using immunofluorescence confocal laser scanning microscopy. Scanning electron microscopy (SEM) was carried out to further determine the ultrastructure of monocyte-RPE adhesion. The results demonstrated that TNF-α modulated inflammatory effects in ARPE-19 by induction of ROS and up-regulation of ICAM-1 expression. Moreover, TNF-α-induced phosphor-NF-κB nuclear translocation, increased phosphor-NF-κB expression and IκB degradation, and increased the degree of monocyte-RPE adhesion. Pretreating the cells with EGCG ameliorated the inflammatory effects of TNF-α. The results indicated that EGCG significantly exerts anti-inflammatory effects in ARPE-19 cells, partly as a suppressor of TNF-α signaling and that the inhibition was mediated via the NF-κB pathway.

  12. HOXB4 homeodomain protein is expressed in developing epidermis and skin disorders and modulates keratinocyte proliferation.

    PubMed

    Kömüves, László G; Michael, Elias; Arbeit, Jeffrey M; Ma, Xiao-Kui; Kwong, Angela; Stelnicki, Eric; Rozenfeld, Sophia; Morimune, M; Yu, Qian-Chun; Largman, Corey

    2002-05-01

    The HOX homeodomain proteins are fundamental regulators of organ and tissue development, where they are thought to function as transcription factors, and HOX gene expression has been associated with numerous types of cancers. Previous studies have demonstrated that enforced expression of the HOXB4 protein transforms cultured fibroblasts and leads to a selective expansion of the hematopoietic stem cell pool, suggesting that this protein might play a role in cellular proliferation. In support of this concept, we now show that enforced expression of HOXB4 in human neonatal keratinocytes results in increased cellular proliferation and colony formation as well as decreased expression of the alpha-2-integrin and CD44 cell surface adhesion molecules. We previously have reported HOXB4 gene expression in the basal and suprabasal layers of developing human skin and now show extensive HOXB4 mRNA in psoriatic skin and basal cell carcinoma. In fetal human skin HOXB4 protein expression was both nuclear and cytoplasmic within epidermal basal cells and in hair follicle inner and outer root sheath cells, whereas strong nuclear signals were observed in the bulge region. In adult skin, HOXB4 protein expression was both nuclear and cytoplasmic, but was predominantly localized to the intermediate and differentiated cell layers. In contrast to the striking gradient patterns of HOX gene and protein expression previously described in developing spinal cord and limb, HOXB4 protein was uniformly detected in all regions of the fetal and adult skin. Although little HOXB4 signal localized to proliferative cell layers, as marked by proliferating cell nuclear antigen (PCNA) staining, in normal adult epidermis, nuclear HOXB4 protein expression substantially overlapped with PCNA-positive cell in a series of samples of hyperproliferative skin. Taken together, these data suggest that nuclear HOXB4 protein may play a role in the regulation of cellular proliferation/adhesion in developing fetal human

  13. Effects of plasma treated PET and PTFE on expression of adhesion molecules by human endothelial cells in vitro.

    PubMed

    Pu, F R; Williams, R L; Markkula, T K; Hunt, J A

    2002-06-01

    The aim of this study was to evaluate the expression of adhesion molecules on the surface of human endothelial cells in response to the systematic variation in materials properties by the ammonia plasma modification of polyethylene terephthalate (PET) and polytetrafluorethylene (PTFE). These adhesion molecules act as mediators of cell adhesion, play a role in the modulation of cell adhesion on biomaterials and therefore condition the response of tissues to implants. First and second passage human umbilical vein endothelial cells (HUVECs) were cultured on plasma treated and untreated PET and PTFE. HUVECs grown on polystyrene tissue culture coverslips and HUVECs stimulated with tumour necrosis factor (TNF-alpha) were used as controls. After 1 day and 7 days, the expression of adhesion molecules platelet endothelial cell adhesion molecule-1 (PECAM-1), intercellular adhesion molecule-1 (ICAM-1), Integrin alphavbeta3, vascular cell adhesion molecule-1 (VCAM-1), E-selectin, P-selectin and L-selectin were evaluated using flow cytometry and immunohistochemistry. There was a slight increase in positive cell numbers expressing the adhesion molecules ICAM-1 and VCAM-1 on plasma treated PET and PTFE. A significant increase in E-selectin positive cells on untreated PTFE was demonstrated after 7 days. Stimulation with TNF-alpha demonstrated a significant increase in the proportion of ICAM-1. VCAM-1 and E-selectin positive cells. Almost all cells expressed PECAM-1 and integrin alphavbeta3, on both materials and controls but did not express P- and L-selectin on any surface. When second passage cells were used, the expression of the adhesion molecules ICAM-1 and VCAM-1 was markedly increased on all surfaces but not with TNF-alpha. These significant differences were not observed in other adhesion molecules. These results were supported by immunohistochemical studies. The effects of plasma treated PET and PTFE on cell adhesion and proliferation was also studied. There was a 1.3-fold

  14. The expression of cytoskeleton regulatory protein Mena in colorectal lesions.

    PubMed

    Gurzu, Simona; Jung, I; Prantner, I; Ember, I; Pávai, Z; Mezei, T

    2008-01-01

    The actin regulatory proteins Ena/VASP (Enabled/Vasodilator stimulated phosphoprotein) family is involved in the control of cell motility and adhesion. They are important in the actin-dependent processes where dynamic actin reorganization it is necessary. The deregulation of actin cycle could have an important role in the cells' malignant transformation, tumor invasion or metastasis. Recently studies revealed that the human orthologue of murine Mena is modulated during the breast carcinogenesis. In our study, we tried to observe the immunohistochemical expression of mammalian Ena (Mena) in the colorectal polyps and carcinomas. We analyzed 10 adenomatous polyps (five with dysplasia) and 36 adenocarcinomas. We used the indirect immunoperoxidase staining. BD Biosciences have provided the Mena antibody. We observed that Mena was not expressed in the normal colorectal mucosa neither in polyps without dysplasia, but its expression was very high in polyps with high dysplasia. In colorectal carcinomas, Mena marked the tumoral cells in 80% of cases. In 25% of positive cases, the intensity was 3+, in 60% 2+ and in the other 15% 1+. The Mena intensity was higher in the microsatellite stable tumors (MSS) and was correlated with vascular invasion, with intensity of angiogenesis marked with CD31 and CD105 and with c-erbB-2 and p53 expression. This is the first study in the literature about Mena expression in colorectal lesions.

  15. De novo expression of intercellular adhesion molecule 1 (ICAM-1, CD54) in pancreas cancer.

    PubMed

    Schwaeble, W; Kerlin, M; Meyer zum Büschenfelde, K H; Dippold, W

    1993-01-21

    We examined the expression of intercellular--adhesion molecule-I (ICAM-I, CD54) in 6 surgically removed pancreatic tumors and 8 pancreatic tumor cell lines. Immunohistochemistry revealed a varying percentage of ICAM-I-positive pancreas tumor cells, while normal pancreatic tissue (except for slight reactivity of endothelial cells) was not stained. The presence of the ICAM-I molecule on the cell surface and the expression of ICAM-I mRNA were investigated for 8 different pancreatic tumor cell lines. Three of these (Capan-I, Capan-2, QGP-I) expressed ICAM-I constitutively. In 4 of the ICAM-I-negative pancreas cancer cell lines, it was possible to induce a remarkable expression of ICAM-I by incubating the cells in the presence of inflammatory cytokines, whereas one cell line, 818-4, remained ICAM-I-negative. The responsiveness to either IFN-gamma, TNF-alpha, or IL-I beta treatment was shown to vary from cell line to cell line, indicating complex mechanisms that regulate the expression of ICAM-I at both, the transcriptional and the post-transcriptional level. Interestingly, ICAM-I is shed by pancreatic tumor cells, since soluble sICAM-I was detected in the cell-culture supernatants. In comparison with normal sera, the mean level of sICAM-I in sera of patients with pancreas carcinoma is elevated 2-fold.

  16. Involvement of small G protein RhoB in the regulation of proliferation, adhesion and migration by dexamethasone in osteoblastic cells

    PubMed Central

    Wang, Yan; Li, Yidong; Xu, Weidong; Lu, Jian

    2017-01-01

    Long-term exposure to therapeutic doses of glucocorticoids (GCs) results in bone remodeling, which frequently causes osteoporosis and fracture healing retardation because of the abnormality of osteoblastic proliferation and differentiation. The mechanisms of GCs’ effect on osteoblasts are largely unknown. In this present study, we found that dexamethasone (Dex) could induce the expression of the small G protein, RhoB, in mRNA and protein levels in the osteoblast-derived osteosarcoma cell lines MG-63. The up-regulation of RhoB mRNA by Dex mainly occurs at posttranscriptional level by increasing its mRNA stability through PI-3K/Akt and p38 mitogen-activated protein kinase signaling pathways. Over-expression of RhoB in MG-63 cells magnified while down-regulation of RhoB level by RNA interference impaired Dex-induced growth inhibition but not differentiation. What’s more, over-expression of RhoB mimicked the effect of Dex on cell adhesion and migration. And interfering RhoB expression partially suppressed Dex-induced pro-adhesion and anti-migration in MG-63 cells. In conclusion, these results indicate that RhoB plays an important role in the pathological effect of Dex on osteoblastic growth and migration, which is a part of the mechanisms of GCs’ adverse effect on bone remodeling. PMID:28323887

  17. Cyclic di-GMP contributes to adaption and virulence of Bacillus thuringiensis through a riboswitch-regulated collagen adhesion protein

    PubMed Central

    Tang, Qing; Yin, Kang; Qian, Hongliang; Zhao, Youwen; Wang, Wen; Chou, Shan-Ho; Fu, Yang; He, Jin

    2016-01-01

    Cyclic di-GMP is a ubiquitous second messenger that regulates diverse cellular processes in bacteria by binding to various protein or riboswitch effectors. In Bacillus thuringiensis BMB171, a c-di-GMP riboswitch termed Bc2 RNA resides in the 5′-untranslated region (5′-UTR) of an mRNA that encodes a collagen adhesion protein (Cap). The expression of cap was strongly repressed in parent strain BMB171 because of the presence of Bc2 RNA but was significantly promoted in the Bc2 RNA markerless deletion mutant. Bc2 RNA acts as a genetic “on” switch, which forms an anti-terminator structure to promote cap read-through transcription upon c-di-GMP binding. As a result, cap transcription was de-repressed under high c-di-GMP levels. Therefore, Bc2 RNA regulates cap expression using a repression/de-repression model. Bc2 RNA-regulated Cap was also found to be tightly associated with motility, aggregation, exopolysaccharide secretion, biofilm formation, and virulence of B. thuringiensis BMB171 against its host insect Helicoverpa armigera. PMID:27381437

  18. Transient Protein Expression by Agroinfiltration in Lettuce.

    PubMed

    Chen, Qiang; Dent, Matthew; Hurtado, Jonathan; Stahnke, Jake; McNulty, Alyssa; Leuzinger, Kahlin; Lai, Huafang

    2016-01-01

    Current systems of recombinant protein production include bacterial, insect, and mammalian cell culture. However, these platforms are expensive to build and operate at commercial scales and/or have limited abilities to produce complex proteins. In recent years, plant-based expression systems have become top candidates for the production of recombinant proteins as they are highly scalable, robust, safe, and can produce complex proteins due to having a eukaryotic endomembrane system. Newly developed "deconstructed" viral vectors delivered via Agrobacterium tumefaciens (agroinfiltration) have enabled robust plant-based production of proteins with a wide range of applications. The leafy Lactuca sativa (lettuce) plant with its strong foundation in agriculture is an excellent host for pharmaceutical protein production. Here, we describe a method for agroinfiltration of lettuce that can rapidly produce high levels of recombinant proteins in a matter of days and has the potential to be scaled up to an agricultural level.

  19. Integral Membrane Protein Expression in Saccharomyces cerevisiae.

    PubMed

    Boswell-Casteel, Rebba C; Johnson, Jennifer M; Stroud, Robert M; Hays, Franklin A

    2016-01-01

    Eukaryotic integral membrane proteins are challenging targets for crystallography or functional characterization in a purified state. Since expression is often a limiting factor when studying this difficult class of biological macromolecules, the intent of this chapter is to focus on the expression of eukaryotic integral membrane proteins (IMPs) using the model organism Saccharomyces cerevisiae. S. cerevisiae is a prime candidate for the expression of eukaryotic IMPs because it offers the convenience of using episomal expression plasmids, selection of positive transformants, posttranslational modifications, and it can properly fold and target IMPs. Here we present a generalized protocol and insights based on our collective knowledge as an aid to overcoming the challenges faced when expressing eukaryotic IMPs in S. cerevisiae.

  20. Transcriptional regulation of adhesive properties of Bacillus subtilis to extracellular matrix proteins through the fibronectin-binding protein YloA.

    PubMed

    Rodriguez Ayala, Facundo; Bauman, Carlos; Bartolini, Marco; Saball, Ester; Salvarrey, Marcela; Leñini, Cecilia; Cogliati, Sebastián; Strauch, Mark; Grau, Roberto

    2017-03-13

    Bacterial adherence to extracellular matrix proteins (ECMp) plays important roles during host-pathogen interaction, however its genetic regulation remains poorly understood. yloA of the model bacterium Bacillus subtilis shows high homology to genes encoding fibronectin-binding proteins of Gram-positive pathogens. Here, we characterized the regulatory network of YloA-dependent adhesive properties of the probiotic B. subtilis natto (Bsn). YloA-proficient, but not YloA-deficient, Bsn specifically bound to ECMp in a concentration-dependent manner and were proficient in biofilm formation. yloA expression showed a continuous increase in activity during the growth phase and decreased during the stationary phase. The transcription factors AbrB and DegU downregulated yloA expression during the logarithmic and stationary growth phases respectively. Analysis of the yloA promoter region revealed the presence of AT-rich direct and inverted repeats previously reported to function as DegU-recognized binding sites. In spo0A cells, yloA expression was completely turned off because of upregulation of AbrB throughout growth. Accordingly, DNase I footprinting analysis confirmed that AbrB bound to the promoter region of yloA. Interestingly, Bsn bound fibronectin with higher affinity, lower Kd, than several bacterial pathogens and competitively excluded them from binding to immobilized-fibronectin, a finding that might be important for the anti-infective properties of B. subtilis and its relatives.

  1. Parallel Control over Surface Charge and Wettability Using Polyelectrolyte Architecture: Effect on Protein Adsorption and Cell Adhesion.

    PubMed

    Guo, Shanshan; Zhu, Xiaoying; Li, Min; Shi, Liya; Ong, June Lay Ting; Jańczewski, Dominik; Neoh, Koon Gee

    2016-11-09

    Surface charge and wettability, the two prominent physical factors governing protein adsorption and cell adhesion, have been extensively investigated in the literature. However, a comparison between these driving forces in terms of their independent and cooperative effects in affecting adhesion is rarely explored on a systematic and quantitative level. Herein, we formulate a protocol that features two-dimensional control over both surface charge and wettability with limited cross-parameter influence. This strategy is implemented by controlling both the polyion charge density in the layer-by-layer (LbL) assembly process and the polyion side-chain chemical structures. The 2D property matrix spans surface isoelectric points ranging from 5 to 9 and water contact angles from 35 to 70°, with other interferential factors (e.g., roughness) eliminated. The interplay between these two surface variables influences protein (bovine serum albumin, lysozyme) adsorption and 3T3 fibroblast cell adhesion. For proteins, we observe the presence of thresholds for surface wettability and electrostatic driving forces necessary to affect adhesion. Beyond these thresholds, the individual effects of electrostatic forces and wettability are observed. For fibroblast, both surface charge and wettability have an effect on its adhesion. The combined effects of positive charge and hydrophilicity lead to the highest cell adhesion, whereas negative charge and hydrophobicity lead to the lowest cell adhesion. Our design strategy can potentially form the basis for studying the distinct behaviors of electrostatic force or wettability driven interfacial phenomena and serve as a reference in future studies assessing protein adsorption and cell adhesion to surfaces with known charge and wettability within the property range studied here.

  2. Interleukin-18-induced cell adhesion molecule expression is associated with feedback regulation by PPAR-γ and NF-κB in Apo E-/- mice.

    PubMed

    Bhat, Owais Mohammad; Uday Kumar, P; Harishankar, N; Ravichandaran, L; Bhatia, A; Dhawan, Veena

    2017-02-07

    Focal recruitment of monocytes and lymphocytes is one of the earliest detectable cellular responses in atherosclerotic lesion formation. Endothelium may regulate leukocyte recruitment by expressing specific adhesion molecules. Interleukin-18 is a proinflammatory cytokine that plays an important role in vascular pathologies. The present study highlights the modulation of adhesion molecules and PPAR-γ by IL-18 and proposes a novel feedback mechanism by which PPAR-γ may regulate IL-18 expression. Three groups of normal chow diet-fed, male Apo E-/- mice, aged 12 weeks (n = 6/group) were employed: Gp I, phosphate-buffered saline (PBS) (2 mo): Gp II, recombinant IL-18 (rIL-18) (1 mo) followed by PBS (1 mo); Gp III, rIL-18 (1 mo) followed by pyrrolidine dithiocarbamate (PDTC) (1 mo). Significantly augmented mRNA expression of ICAM-1 (~5.7-fold), VCAM-1 (~3.6-fold), and NF-κB (~7-fold) was observed in Gp II mice as compared to Gp I, whereas PPAR-γ expression was not altered. PDTC treatment caused a significant downregulation of ICAM-1 (~4.2-fold), VCAM-1(~2-fold), and NF-κB (~4.5-fold) and upregulation of PPAR-γ expression (~5-fold) in Gp III mice. A similar trend was observed in protein expression. In vivo imaging results demonstrated a marked increase in probe (CF750 dye conjugated to VCAM-1 antibody) fluorescence intensity for VCAM-1 expression in Gp II mice, whereas it was moderately decreased in Gp III. PPAR-γ was found to significantly downregulate both IL-18 levels and IL-18-induced adhesion molecules. The underlying mechanism was found to be via inhibition of NF-κB activity by PDTC, thereby leading to decreased adherence of monocytes to the activated endothelial cells and a step to halt the progression and development of atherosclerotic lesions.

  3. Biotechnology Protein Expression and Purification Facility

    NASA Technical Reports Server (NTRS)

    2003-01-01

    The purpose of the Project Scientist Core Facility is to provide purified proteins, both recombinant and natural, to the Biotechnology Science Team Project Scientists and the NRA-Structural Biology Test Investigators. Having a core facility for this purpose obviates the need for each scientist to develop the necessary expertise and equipment for molecular biology, protein expression, and protein purification. Because of this, they are able to focus their energies as well as their funding on the crystallization and structure determination of their target proteins.

  4. Amyloid precursor-like protein 1 (APLP1) exhibits stronger zinc-dependent neuronal adhesion than amyloid precursor protein and APLP2.

    PubMed

    Mayer, Magnus C; Schauenburg, Linda; Thompson-Steckel, Greta; Dunsing, Valentin; Kaden, Daniela; Voigt, Philipp; Schaefer, Michael; Chiantia, Salvatore; Kennedy, Timothy E; Multhaup, Gerhard

    2016-04-01

    The amyloid precursor protein (APP) and its paralogs, amyloid precursor-like protein 1 (APLP1) and APLP2, are metalloproteins with a putative role both in synaptogenesis and in maintaining synapse structure. Here, we studied the effect of zinc on membrane localization, adhesion, and secretase cleavage of APP, APLP1, and APLP2 in cell culture and rat neurons. For this, we employed live-cell microscopy techniques, a microcontact printing adhesion assay and ELISA for protein detection in cell culture supernatants. We report that zinc induces the multimerization of proteins of the amyloid precursor protein family and enriches them at cellular adhesion sites. Thus, zinc facilitates the formation of de novo APP and APLP1 containing adhesion complexes, whereas it does not have such influence on APLP2. Furthermore, zinc-binding prevented cleavage of APP and APLPs by extracellular secretases. In conclusion, the complexation of zinc modulates neuronal functions of APP and APLPs by (i) regulating formation of adhesion complexes, most prominently for APLP1, and (ii) by reducing the concentrations of neurotrophic soluble APP/APLP ectodomains. Earlier studies suggest a function of the amyloid precursor protein (APP) family proteins in neuronal adhesion. We report here that adhesive function of these proteins is tightly regulated by zinc, most prominently for amyloid precursor-like protein 1 (APLP1). Zinc-mediated APLP1 multimerization, which induced formation of new neuronal contacts and decreased APLP1 shedding. This suggests that APLP1 could function as a zinc receptor processing zinc signals to stabilized or new neuronal contacts.

  5. PM2.5-induced oxidative stress increases adhesion molecules expression in human endothelial cells through the ERK/AKT/NF-κB-dependent pathway.

    PubMed

    Rui, Wei; Guan, Longfei; Zhang, Fang; Zhang, Wei; Ding, Wenjun

    2016-01-01

    The aim of this study was to explore the intracellular mechanisms underlying the cardiovascular toxicity of air particulate matter (PM) with an aerodynamic diameter of less than 2.5 µm (PM2.5) in a human umbilical vein cell line, EA.hy926. We found that PM2.5 exposure triggered reactive oxygen species (ROS) generation, resulting in a significant decrease in cell viability. Data from Western blots showed that PM2.5 induced phosphorylation of Jun N-terminal kinase (JNK), extracellular signal regulatory kinase (ERK), p38 mitogen-activated protein kinase (MAPK) and protein kinase B (AKT), and activation of nuclear factor kappa B (NF-κB). We further observed a significant increase in expressions of intercellular adhesion molecule-1 (ICAM-1) and vascular adhesion molecule-1 (VCAM-1) in a time- and dose-dependent manner. Moreover, the adhesion of monocytic THP-1 cells to EA.hy926 cells was greatly enhanced in the presence of PM2.5 . However, N-acetylcysteine (NAC), a scavenger of ROS, prevented the increase of ROS generation, attenuated the phosphorylation of the above kinases, and decreased the NF-κB activation as well as the expression of ICAM-1 and VCAM-1. Furthermore, ERK inhibitor (U0126), AKT inhibitor (LY294002) and NF-κB inhibitor (BAY11-7082) significantly down-regulated PM2.5 -induced ICAM-1 and VCAM-1 expression as well as adhesion of THP-1 cells, but not JNK inhibitor (SP600125) and p38 MAPK inhibitor (SB203580), indicating that ERK/AKT/NF-κB is involved in the signaling pathway that leads to PM2.5 -induced ICAM-1 and VCAM-1 expression. These findings suggest PM2.5 -induced ROS may function as signaling molecules triggering ICAM-1 and VCAM-1 expressions through activating the ERK/AKT/NF-κB-dependent pathway, and further promoting monocyte adhesion to endothelial cells.

  6. The N Terminus of the Prion Protein Mediates Functional Interactions with the Neuronal Cell Adhesion Molecule (NCAM) Fibronectin Domain.

    PubMed

    Slapšak, Urška; Salzano, Giulia; Amin, Ladan; Abskharon, Romany N N; Ilc, Gregor; Zupančič, Blaž; Biljan, Ivana; Plavec, Janez; Giachin, Gabriele; Legname, Giuseppe

    2016-10-14

    The cellular form of the prion protein (PrP(C)) is a highly conserved glycoprotein mostly expressed in the central and peripheral nervous systems by different cell types in mammals. A misfolded, pathogenic isoform, denoted as prion, is related to a class of neurodegenerative diseases known as transmissible spongiform encephalopathy. PrP(C) function has not been unequivocally clarified, and it is rather defined as a pleiotropic protein likely acting as a dynamic cell surface scaffolding protein for the assembly of different signaling modules. Among the variety of PrP(C) protein interactors, the neuronal cell adhesion molecule (NCAM) has been studied in vivo, but the structural basis of this functional interaction is still a matter of debate. Here we focused on the structural determinants responsible for human PrP(C) (HuPrP) and NCAM interaction using stimulated emission depletion (STED) nanoscopy, SPR, and NMR spectroscopy approaches. PrP(C) co-localizes with NCAM in mouse hippocampal neurons, and this interaction is mainly mediated by the intrinsically disordered PrP(C) N-terminal tail, which binds with high affinity to the NCAM fibronectin type-3 domain. NMR structural investigations revealed surface-interacting epitopes governing the interaction between HuPrP N terminus and the second module of the NCAM fibronectin type-3 domain. Our data provided molecular details about the interaction between HuPrP and the NCAM fibronectin domain, and revealed a new role of PrP(C) N terminus as a dynamic and functional element responsible for protein-protein interaction.

  7. Cyclosporin A reduces expression of adhesion molecules in the kidney of rats with chronic serum sickness

    PubMed Central

    Rincón, J; Parra, G; Quiroz, Y; Benatuil, L; Rodríguez-Iturbe, B

    2000-01-01

    Treatment with cyclosporin A (CsA) improves proteinuria and reduces renal cellular infiltration in chronic serum sickness (CSS). We examined if these effects were associated with a reduced renal expression of CD54 and its ligands, interferon-gamma (IFN-γ), tumour necrosis factor-alpha (TNF-α) and MHC class II molecules. We studied two groups of rats in which CSS was induced by daily injections of ovalbumin (OVA): a group treated with CsA (OVA.CsA group, n = 11) and a group that received no treatment (OVA.CSS group, n = 11). An additional group of five rats (control group) received only phosphate buffer. Immunostaining techniques were used to follow CSS and to study the expression of CD54, CD18, CD11b/c, IFN-γ, TNF-α and MHC class molecules. Proteinuria (mg/24 h) was reduced from 248·2 ± 73·1 (OVA.CCS group) to 14·5 ± 13·1 with CsA treatment (P < 0·0001). The renal expression of CD54 and its ligands (CD18 and CD11b/c) was reduced by 50% to 75%. Correspondingly, there was a 60% to 85% reduction in the number of infiltrating leucocytes. The number of cells expressing TNF-α, IFN-γ and MHC II molecules was also reduced. CsA reduces expression of CD54 and its ligands. This effect is associated with a reduction of cellular infiltration, IFN-γ, TNF-α-producing cells and with MHC II expression in the kidney. These findings suggest that expression of adhesion molecules plays a critical role in CSS and underline the importance of cellular immunity in this experimental model. PMID:10931158

  8. Nanospherical arabinogalactan proteins are a key component of the high-strength adhesive secreted by English ivy

    PubMed Central

    Huang, Yujian; Wang, Yongzhong; Tan, Li; Sun, Leming; Petrosino, Jennifer; Cui, Mei-Zhen; Hao, Feng; Zhang, Mingjun

    2016-01-01

    Over 130 y have passed since Charles Darwin first discovered that the adventitious roots of English ivy (Hedera helix) exude a yellowish mucilage that promotes the capacity of this plant to climb vertical surfaces. Unfortunately, little progress has been made in elucidating the adhesion mechanisms underlying this high-strength adhesive. In the previous studies, spherical nanoparticles were observed in the viscous exudate. Here we show that these nanoparticles are predominantly composed of arabinogalactan proteins (AGPs), a superfamily of hydroxyproline-rich glycoproteins present in the extracellular spaces of plant cells. The spheroidal shape of the AGP-rich ivy nanoparticles results in a low viscosity of the ivy adhesive, and thus a favorable wetting behavior on the surface of substrates. Meanwhile, calcium-driven electrostatic interactions among carboxyl groups of the AGPs and the pectic acids give rise to the cross-linking of the exuded adhesive substances, favor subsequent curing (hardening) via formation of an adhesive film, and eventually promote the generation of mechanical interlocking between the adventitious roots of English ivy and the surface of substrates. Inspired by these molecular events, a reconstructed ivy-mimetic adhesive composite was developed by integrating purified AGP-rich ivy nanoparticles with pectic polysaccharides and calcium ions. Information gained from the subsequent tensile tests, in turn, substantiated the proposed adhesion mechanisms underlying the ivy-derived adhesive. Given that AGPs and pectic polysaccharides are also observed in bioadhesives exuded by other climbing plants, the adhesion mechanisms revealed by English ivy may forward the progress toward understanding the general principles underlying diverse botanic adhesives. PMID:27217558

  9. Nanospherical arabinogalactan proteins are a key component of the high-strength adhesive secreted by English ivy

    NASA Astrophysics Data System (ADS)

    Huang, Yujian; Wang, Yongzhong; Tan, Li; Sun, Leming; Petrosino, Jennifer; Cui, Mei-Zhen; Hao, Feng; Zhang, Mingjun

    2016-06-01

    Over 130 y have passed since Charles Darwin first discovered that the adventitious roots of English ivy (Hedera helix) exude a yellowish mucilage that promotes the capacity of this plant to climb vertical surfaces. Unfortunately, little progress has been made in elucidating the adhesion mechanisms underlying this high-strength adhesive. In the previous studies, spherical nanoparticles were observed in the viscous exudate. Here we show that these nanoparticles are predominantly composed of arabinogalactan proteins (AGPs), a superfamily of hydroxyproline-rich glycoproteins present in the extracellular spaces of plant cells. The spheroidal shape of the AGP-rich ivy nanoparticles results in a low viscosity of the ivy adhesive, and thus a favorable wetting behavior on the surface of substrates. Meanwhile, calcium-driven electrostatic interactions among carboxyl groups of the AGPs and the pectic acids give rise to the cross-linking of the exuded adhesive substances, favor subsequent curing (hardening) via formation of an adhesive film, and eventually promote the generation of mechanical interlocking between the adventitious roots of English ivy and the surface of substrates. Inspired by these molecular events, a reconstructed ivy-mimetic adhesive composite was developed by integrating purified AGP-rich ivy nanoparticles with pectic polysaccharides and calcium ions. Information gained from the subsequent tensile tests, in turn, substantiated the proposed adhesion mechanisms underlying the ivy-derived adhesive. Given that AGPs and pectic polysaccharides are also observed in bioadhesives exuded by other climbing plants, the adhesion mechanisms revealed by English ivy may forward the progress toward understanding the general principles underlying diverse botanic adhesives.

  10. Tethered agonists: a new mechanism underlying adhesion G protein-coupled receptor activation.

    PubMed

    Schöneberg, Torsten; Liebscher, Ines; Luo, Rong; Monk, Kelly R; Piao, Xianhua

    2015-06-01

    The family of adhesion G protein-coupled receptors (aGPCRs) comprises 33 members in the human genome, which are subdivided into nine subclasses. Many aGPCRs undergo an autoproteolytic process via their GPCR Autoproteolysis-INducing (GAIN) domain during protein maturation to generate an N- and a C-terminal fragments, NTF and CTF, respectively. The NTF and CTF are non-covalently reassociated on the plasma membrane to form a single receptor unit. How aGPCRs are activated upon ligand binding remains one of the leading questions in the field of aGPCR research. Recent work from our labs and others shows that ligand binding can remove the NTF from the plasma membrane-bound CTF, exposing a tethered agonist which potently activates downstream signaling.

  11. Spatiotemporal segregation of endothelial cell integrin and nonintegrin extracellular matrix-binding proteins during adhesion events

    PubMed Central

    1990-01-01

    Bovine aortic endothelial cell (BAEC) attachments to laminin, fibronectin, and fibrinogen are inhibited by soluble arginine-glycine- aspartate (RGD)-containing peptides, and YGRGDSP activity is responsive to titration of either soluble peptide or matrix protein. To assess the presence of RGD-dependent receptors, immunoprecipitation and immunoblotting studies were conducted and demonstrated integrin beta 1, beta 3, and associated alpha subunits as well as a beta 1 precursor. Immunofluorescence of BAECs plated on laminin, fibronectin, and fibrinogen reveals different matrix-binding specificities of each of these integrin subclasses. By 1 h after plating, organization of beta 1 integrin into fibrillar streaks is influenced by laminin and fibronectin, whereas beta 3 integrin punctate organization is influenced by fibrinogen and the integrin spatial distribution changes with time in culture. In contrast, the nonintegrin laminin-binding protein LB69 only organizes after cell-substrate contact is well established several hours after plating. Migration of BAECs is also mediated by both integrin and nonintegrin matrix-binding proteins. Specifically, BAEC migration on laminin is remarkably sensitive to RGD peptide inhibition, and, in its presence, beta 1 integrin organization dissipates and reorganizes into perinuclear vesicles. However, RGD peptides do not alter LB69 linear organization during migration. Similarly, agents that block LB69--e.g., antibodies to LB69 as well as YIGSR-NH2 peptide--do not inhibit attachment of nonmotile BAECs to laminin. However, both anti-LB69 and YIGSR-NH2 inhibit late adhesive events such as spreading. Accordingly, we propose that integrin and nonintegrin extracellular matrix-binding protein organizations in BAECs are both temporally and spatially segregated during attachment processes. High affinity nonintegrin interaction with matrix may create necessary stable contacts for longterm attachment, while lower affinity integrins may be important

  12. Understanding Marine Mussel Adhesion

    SciTech Connect

    H. G. Silverman; F. F. Roberto

    2007-12-01

    In addition to identifying the proteins that have a role in underwater adhesion by marine mussels, research efforts have focused on identifying the genes responsible for the adhesive proteins, environmental factors that may influence protein production, and strategies for producing natural adhesives similar to the native mussel adhesive proteins. The production-scale availability of recombinant mussel adhesive proteins will enable researchers to formulate adhesives that are waterimpervious and ecologically safe and can bind materials ranging from glass, plastics, metals, and wood to materials, such as bone or teeth, biological organisms, and other chemicals or molecules. Unfortunately, as of yet scientists have been unable to duplicate the processes that marine mussels use to create adhesive structures. This study provides a background on adhesive proteins identified in the blue mussel, Mytilus edulis, and introduces our research interests and discusses the future for continued research related to mussel adhesion.

  13. Understanding Marine Mussel Adhesion

    PubMed Central

    Roberto, Francisco F.

    2007-01-01

    In addition to identifying the proteins that have a role in underwater adhesion by marine mussels, research efforts have focused on identifying the genes responsible for the adhesive proteins, environmental factors that may influence protein production, and strategies for producing natural adhesives similar to the native mussel adhesive proteins. The production-scale availability of recombinant mussel adhesive proteins will enable researchers to formulate adhesives that are water-impervious and ecologically safe and can bind materials ranging from glass, plastics, metals, and wood to materials, such as bone or teeth, biological organisms, and other chemicals or molecules. Unfortunately, as of yet scientists have been unable to duplicate the processes that marine mussels use to create adhesive structures. This study provides a background on adhesive proteins identified in the blue mussel, Mytilus edulis, and introduces our research interests and discusses the future for continued research related to mussel adhesion. PMID:17990038

  14. Bordetella pertussis infection of human respiratory epithelial cells up-regulates intercellular adhesion molecule-1 expression: role of filamentous hemagglutinin and pertussis toxin.

    PubMed

    Ishibashi, Yoshio; Nishikawa, Akemi

    2002-09-01

    Adhesion molecules on respiratory epithelial cells play a critical role in inflammatory cell recruitment and accumulation at sites of inflammation. Bordetella pertussis colonizes the human respiratory tract by infecting epithelial cells, leading to an inflammatory response. In this study, the role of bacterial factors in the expression of intercellular adhesion molecule-1 (ICAM-1) on human respiratory epithelial cells was investigated in response to B. pertussis. Flow cytometry and real time RT-PCR analysis showed that BEAS-2B human bronchial epithelial cells expressed increased levels of ICAM-1 mRNA and surface protein in response to B. pertussis infection. Filamentous hemagglutinin (FHA) played a role in this response because of the impaired capability of a FHA-deficient isogenic strain. A mutant strain in which an Arg-Gly-Asp (RGD) site of FHA had been changed to Arg-Ala-Asp had diminished ability to up-regulate ICAM-1 expression. RGD sequence-associated up-regulation of ICAM-1 expression was also observed in primary normal human bronchial epithelial cells. Pretreatment of cells with integrin antagonists such as RGD-containing peptide and antibody against very late antigen-5 (VLA-5) inhibited the up-regulation of ICAM-1 expression, suggesting the participation of VLA-5 integrin in this response. Pertussis toxin (PT) prevented the up-regulation of ICAM-1 expression because a PT-deficient mutant strain induced higher levels of ICAM-1 mRNA and surface protein than the parental strain. Consistent with this, purified PT suppressed the up-regulation of epithelial ICAM-1 expression. These findings demonstrate that B. pertussis FHA up-regulates ICAM-1 expression on respiratory epithelial cells through interaction of its RGD site with host cell VLA-5 integrin, and that PT impairs this response.

  15. Protein Kinase D1 regulates focal adhesion dynamics and cell adhesion through Phosphatidylinositol-4-phosphate 5-kinase type-l γ

    PubMed Central

    Durand, Nisha; Bastea, Ligia I.; Long, Jason; Döppler, Heike; Ling, Kun; Storz, Peter

    2016-01-01

    Focal adhesions (FAs) are highly dynamic structures that are assembled and disassembled on a continuous basis. The balance between the two processes mediates various aspects of cell behavior, ranging from cell adhesion and spreading to directed cell migration. The turnover of FAs is regulated at multiple levels and involves a variety of signaling molecules and adaptor proteins. In the present study, we show that in response to integrin engagement, a subcellular pool of Protein Kinase D1 (PKD1) localizes to the FAs. PKD1 affects FAs by decreasing turnover and promoting maturation, resulting in enhanced cell adhesion. The effects of PKD1 are mediated through direct phosphorylation of FA-localized phosphatidylinositol-4-phosphate 5-kinase type-l γ (PIP5Klγ) at serine residue 448. This phosphorylation occurs in response to Fibronectin-RhoA signaling and leads to a decrease in PIP5Klγs’ lipid kinase activity and binding affinity for Talin. Our data reveal a novel function for PKD1 as a regulator of FA dynamics and by identifying PIP5Klγ as a novel PKD1 substrate provide mechanistic insight into this process. PMID:27775029

  16. Protein Kinase D1 regulates focal adhesion dynamics and cell adhesion through Phosphatidylinositol-4-phosphate 5-kinase type-l γ.

    PubMed

    Durand, Nisha; Bastea, Ligia I; Long, Jason; Döppler, Heike; Ling, Kun; Storz, Peter

    2016-10-24

    Focal adhesions (FAs) are highly dynamic structures that are assembled and disassembled on a continuous basis. The balance between the two processes mediates various aspects of cell behavior, ranging from cell adhesion and spreading to directed cell migration. The turnover of FAs is regulated at multiple levels and involves a variety of signaling molecules and adaptor proteins. In the present study, we show that in response to integrin engagement, a subcellular pool of Protein Kinase D1 (PKD1) localizes to the FAs. PKD1 affects FAs by decreasing turnover and promoting maturation, resulting in enhanced cell adhesion. The effects of PKD1 are mediated through direct phosphorylation of FA-localized phosphatidylinositol-4-phosphate 5-kinase type-l γ (PIP5Klγ) at serine residue 448. This phosphorylation occurs in response to Fibronectin-RhoA signaling and leads to a decrease in PIP5Klγs' lipid kinase activity and binding affinity for Talin. Our data reveal a novel function for PKD1 as a regulator of FA dynamics and by identifying PIP5Klγ as a novel PKD1 substrate provide mechanistic insight into this process.

  17. Role of the actin-binding protein profilin1 in radial migration and glial cell adhesion of granule neurons in the cerebellum.

    PubMed

    Rust, Marco B; Kullmann, Jan A; Witke, Walter

    2012-01-01

    Profilins are small G-actin-binding proteins essential for cytoskeletal dynamics. Of the four mammalian profilin isoforms, profilin1 shows a broad expression pattern, profilin2 is abundant in the brain, and profilin3 and profilin4 are restricted to the testis. In vitro studies on cancer and epithelial cell lines suggested a role for profilins in cell migration and cell-cell adhesion. Genetic studies in mice revealed the importance of profilin1 in neuronal migration, while profilin2 has apparently acquired a specific function in synaptic physiology. We recently reported a mouse mutant line lacking profilin1 in the brain; animals display morphological defects that are typical for impaired neuronal migration. We found that during cerebellar development, profilin1 is specifically required for radial migration and glial cell adhesion of granule neurons. Profilin1 mutants showed cerebellar hypoplasia and aberrant organization of cerebellar cortex layers, with ectopically arranged granule neurons. In this commentary, we briefly introduce the profilin family and summarize the current knowledge on profilin activity in cell migration and adhesion. Employing cerebellar granule cells as a model, we shed some light on the mechanisms by which profilin1 may control radial migration and glial cell adhesion. Finally, a potential implication of profilin1 in human developmental neuropathies is discussed.

  18. Arabidopsis NDR1 is an integrin-like protein with a role in fluid loss and plasma membrane-cell wall adhesion.

    PubMed

    Knepper, Caleb; Savory, Elizabeth A; Day, Brad

    2011-05-01

    Arabidopsis (Arabidopsis thaliana) NON-RACE-SPECIFIC DISEASE RESISTANCE1 (NDR1), a plasma membrane-localized protein, plays an essential role in resistance mediated by the coiled-coil-nucleotide-binding site-leucine-rich repeat class of resistance (R) proteins, which includes RESISTANCE TO PSEUDOMONAS SYRINGAE2 (RPS2), RESISTANCE TO PSEUDOMONAS SYRINGAE PV MACULICOLA1, and RPS5. Infection with Pseudomonas syringae pv tomato DC3000 expressing the bacterial effector proteins AvrRpt2, AvrB, and AvrPphB activates resistance by the aforementioned R proteins. Whereas the genetic requirement for NDR1 in plant disease resistance signaling has been detailed, our study focuses on determining a global, physiological role for NDR1. Through the use of homology modeling and structure threading, NDR1 was predicted to have a high degree of structural similarity to Arabidopsis LATE EMBRYOGENESIS ABUNDANT14, a protein implicated in abiotic stress responses. Specific protein motifs also point to a degree of homology with mammalian integrins, well-characterized proteins involved in adhesion and signaling. This structural homology led us to examine a physiological role for NDR1 in preventing fluid loss and maintaining cell integrity through plasma membrane-cell wall adhesions. Our results show a substantial alteration in induced (i.e. pathogen-inoculated) electrolyte leakage and a compromised pathogen-associated molecular pattern-triggered immune response in ndr1-1 mutant plants. As an extension of these analyses, using a combination of genetic and cell biology-based approaches, we have identified a role for NDR1 in mediating plasma membrane-cell wall adhesions. Taken together, our data point to a broad role for NDR1 both in mediating primary cellular functions in Arabidopsis through maintaining the integrity of the cell wall-plasma membrane connection and as a key signaling component of these responses during pathogen infection.

  19. Recombinant mussel adhesive protein fp-5 (MAP fp-5) as a bulk bioadhesive and surface coating material.

    PubMed

    Choi, Yoo Seong; Kang, Dong Gyun; Lim, Seonghye; Yang, Yun Jung; Kim, Chang Sup; Cha, Hyung Joon

    2011-08-01

    Mussel adhesive proteins (MAPs) attach to all types of inorganic and organic surfaces, even in wet environments. MAP of type 5 (fp-5), in particular, has been considered as a key adhesive material. However, the low availability of fp-5 has hampered its biochemical characterization and practical applications. Here, soluble recombinant fp-5 is mass-produced in Escherichia coli. Tyrosinase-modified recombinant fp-5 showed ∼1.11 MPa adhesive shear strength, which is the first report of a bulk-scale adhesive force measurement for purified recombinant of natural MAP type. Surface coatings were also performed through simple dip-coating of various objects. In addition, complex coacervate using recombinant fp-5 and hyaluronic acid was prepared as an efficient adhesive formulation, which greatly improved the bulk adhesive strength. Collectively, it is expected that this work will enhance basic understanding of mussel adhesion and that recombinant fp-5 can be successfully used as a realistic bulk-scale bioadhesive and an efficient surface coating material.

  20. Platelet adhesion and protein adsorption on silicone rubber surface by ozone-induced grafted polymerization with carboxybetaine monomer.

    PubMed

    Zhou, Jun; Yuan, Jiang; Zang, Xiaopeng; Shen, Jian; Lin, Sicong

    2005-03-10

    Platelet adhesion and protein adsorption on the silicone rubber film grafted with N,N'-dimethyl-N-methacryloyloxyethyl-N-(2-carboxyethyl) ammonium (DMMCA) was studied. The grafting was carried out by means of ozone-induced method and was confirmed by ATR-FTIR and XPS investigations. The grafted films possessed relatively hydrophilic surface revealed by contact angle measurement. The blood compatibility of the grafted film was evaluated in vitro by platelet adhesion in platelet-rich plasma (PRP) and protein absorption in bovine fibrinogen (BFG) using silicone film as the reference. No substantial platelet adhesion was observed for the grafted films incubated in PRP for 60 and 180 min. The protein absorption was also significantly reduced after incubated in bovine fibrinogen for 60 min. Both the results indicated that the blood compatibility of silicone rubber was greatly improved by ozone-induced grafting of carboxybetaine zwitterionic polymer onto its surface.

  1. Eotaxin increases the expression of CD11b/CD18 and adhesion properties in IL5, but not fMLP-prestimulated human peripheral blood eosinophils.

    PubMed

    Lundahl, J; Moshfegh, A; Grönneberg, R; Halldén, G

    1998-04-01

    A selective recruitment of eosinophils to sites of inflammation is claimed to be controlled by regulation of cytokines, chemokines and adhesion molecules. In animal models, eotaxin has been suggested to be a potent chemokine since it in cooperation with interleukin-5 induce selective chemotaxis and infiltration of eosinophils to lung tissue after an allergen provocation. We have investigated the in vitro effect of eotaxin on human peripheral blood eosinophils with respect to CD11b/CD18 expression and adhesion properties to the matrix protein fibronectin. We did not find any effect of eotaxin per se on CD11b/CD18 expression, neither on eosinophils from healthy subjects nor from patients with asymptomatic pollen related asthma. However, eotaxin significantly upregulated the quantitative level of CD11b/CD18 and increased the adhesion to fibronectin in eosinophils from healthy subjects preincubated in vitro with interleukin-5, but not in eosinophils preincubated with fMLP. Moreover, eosinophils harvested 24 hours after an in vivo allergen inhalation provocation in asthmatics, upregulated CD11b/CD18 after in vitro incubation with eotaxin alone.

  2. Zeb1 Regulates E-cadherin and Epcam (Epithelial Cell Adhesion Molecule) Expression to Control Cell Behavior in Early Zebrafish Development*

    PubMed Central

    Vannier, Corinne; Mock, Kerstin; Brabletz, Thomas; Driever, Wolfgang

    2013-01-01

    The ZEB1 transcription factor is best known as an inducer of epithelial-mesenchymal transitions (EMT) in cancer metastasis, acting through transcriptional repression of CDH1 (encoding E-cadherin) and the EMT-suppressing microRNA-200s (miR-200s). Here we analyze roles of the ZEB1 zebrafish orthologs, Zeb1a and Zeb1b, and of miR-200s in control of cell adhesion and morphogenesis during gastrulation and segmentation stages. Loss and gain of function analyses revealed that Zeb1 represses cdh1 expression to fine-tune adhesiveness of migrating deep blastodermal cells. Furthermore, Zeb1 acts as a repressor of epcam in the deep cells of the blastoderm and may contribute to control of epithelial integrity of enveloping layer cells, the outermost cells of the blastoderm. We found a similar ZEB1-dependent repression of EPCAM expression in human pancreatic and breast cancer cell lines, mediated through direct binding of ZEB1 to the EPCAM promoter. Thus, Zeb1 proteins employ several evolutionary conserved mechanisms to regulate cell-cell adhesion during development and cancer. PMID:23667256

  3. Epidermal Expression of Intercellular Adhesion Molecule 1 is Not a Primary Inducer of Cutaneous Inflammation in Transgenic Mice

    NASA Astrophysics Data System (ADS)

    Williams, Ifor R.; Kupper, Thomas S.

    1994-10-01

    Keratinocytes at sites of cutaneous inflammation have increased expression of intercellular adhesion molecule 1 (ICAM-1), a cytokine-inducible adhesion molecule which binds the leukocyte integrins LFA-1 and Mac-1. Transgenic mice were prepared in which the expression of mouse ICAM-1 was targeted to basal keratinocytes by using the human K14 keratin promoter. The level of constitutive expression attained in the transgenic mice exceeded the peak level of ICAM-1 expression induced on nontransgenic mouse keratinocytes in vitro by optimal combinations of interferon γ and tumor necrosis factor α or in vivo by proinflammatory stimuli such as phorbol 12-myristate 13-acetate. In vitro adhesion assays demonstrated that cultured transgenic keratinocytes were superior to normal keratinocytes as a substrate for the LFA-1-dependent binding of mouse T cells, confirming that the transgene-encoded ICAM-1 was expressed in a functional form. However, the high level of constitutive ICAM-1 expression achieved on keratinocytes in vivo in these transgenic mice did not result in additional recruitment of CD45^+ leukocytes into transgenic epidermis, nor did it elicit dermal inflammation. Keratinocyte ICAM-1 expression also did not potentiate contact-hypersensitivity reactions to epicutaneous application of haptens. The absence of a spontaneous phenotype in these transgenic mice was not the result of increased levels of soluble ICAM-1, since serum levels of soluble ICAM-1 were equal in transgenic mice and controls. We conclude that elevated ICAM-1 expression on keratinocytes cannot act independently to influence leukocyte trafficking and elicit cutaneous inflammation.

  4. The involvement of an integrin-like protein and protein kinase C in amoebic adhesion to fibronectin and amoebic cytotoxicity.

    PubMed

    Han, Kyu-Lee; Lee, Hyun-Ju; Shin, Myeong Heon; Shin, Ho-Joon; Im, Kyung-Il; Park, Soon-Jung

    2004-09-01

    Adherence of a pathogen to the host cell is one of the critical steps in microbial infections. Naegleria fowleri, a causative agent of primary amoebic meningoencephalitis in humans, is expected to interact with extracellular components of the host, such as fibronectin, in a receptor-mediated mode. In this study, we investigated the interaction between N. fowleri and fibronectin to understand its cytopathology. In binding assays using immobilized fibronectin, the number of amoebae bound to fibronectin was increased compared to the controls, and was dependent on the amount of coated fibronectin present. A fibronectin binding protein of 60 kDa was found in extracts of N. fowleri. Western blot and immunolocalization assays using integrin alpha(5)/FnR antibodies showed that a 60 kDa protein reacted with the antibodies in extracts of N. fowleri, which was localized on the surface of N. fowleri. Preincubation of N. fowleri with the integrin antibodies significantly inhibited amoebic binding to fibronectin and cytotoxicity to the CHO cells. Additionally, protein kinase C activity was detected in the extract of N. fowleri. When N. fowleri was pretreated with protein kinase C activator or inhibitor, the abilities of amoebic adhesion to fibronectin and cytotoxicity to the host cells were markedly affected compared to untreated amoebae. These results suggest that an amoebic integrin-like receptor and protein kinase C play important roles in amoebic cellular processes in response to fibronectin.

  5. Expression Level of Genes Coding for Cell Adhesion Molecules of Cadherin Group in Colorectal Cancer Patients

    PubMed Central

    Lorenc, Zbigniew; Opiłka, Mieszko Norbert; Kruszniewska-Rajs, Celina; Rajs, Antoni; Waniczek, Dariusz; Starzewska, Małgorzata; Lorenc, Justyna; Mazurek, Urszula

    2015-01-01

    Background Colorectal Cancer (CRC) is one of the most frequently diagnosed neoplasms and also one of the main death causes. Cell adhesion molecules are taking part in specific junctions, contributing to tissue integrality. Lower expression of the cadherins may be correlated with poorer differentiation of the CRC, and its more aggressive phenotype. The aim of the study is to designate the cadherin genes potentially useful for the diagnostics, prognostics, and the treatment of CRC. Material/Method Specimens were collected from 28 persons (14 female and 14 male), who were operated for CRC. The molecular analysis was performed using oligonucleotide microarrays, mRNA used was collected from adenocarcinoma, and macroscopically healthy tissue. The results were validated using qRT-PCR technique. Results Agglomerative hierarchical clustering of normalized mRNA levels has shown 4 groups with statistically different gene expression. The control group was divided into 2 groups, the one was appropriate control (C1), the second (C2) had the genetic properties of the CRC, without pathological changes histologically and macroscopically. The other 2 groups were: LSC (Low stage cancer) and HSC (High stage cancer). Consolidated results of the fluorescency of all of the differential genes, designated two coding E-cadherin (CDH1) with the lower expression, and P-cadherin (CDH3) with higher expression in CRC tissue. Conclusions The levels of genes expression are different for several groups of cadherins, and are related with the stage of CRC, therefore could be potentially the useful marker of the stage of the disease, also applicable in treatment and diagnostics of CRC. PMID:26167814

  6. Unraveling the Role of Surface Mucus-Binding Protein and Pili in Muco-Adhesion of Lactococcus lactis

    PubMed Central

    Duviau, Marie-Pierre; Meyrand, Mickael; Guérardel, Yann; Castelain, Mickaël; Loubière, Pascal; Chapot-Chartier, Marie-Pierre; Dague, Etienne; Mercier-Bonin, Muriel

    2013-01-01

    Adhesion of bacteria to mucus may favor their persistence within the gut and their beneficial effects to the host. Interactions between pig gastric mucin (PGM) and a natural isolate of Lactococcus lactis (TIL448) were measured at the single-cell scale and under static conditions, using atomic force microscopy (AFM). In parallel, these interactions were monitored at the bacterial population level and under shear flow. AFM experiments with a L. lactis cell-probe and a PGM-coated surface revealed a high proportion of specific adhesive events (60%) and a low level of non-adhesive ones (2%). The strain muco-adhesive properties were confirmed by the weak detachment of bacteria from the PGM-coated surface under shear flow. In AFM, rupture events were detected at short (100−200 nm) and long distances (up to 600−800 nm). AFM measurements on pili and mucus-binding protein defective mutants demonstrated the comparable role played by these two surface proteinaceous components in adhesion to PGM under static conditions. Under shear flow, a more important contribution of the mucus-binding protein than the pili one was observed. Both methods differ by the way of probing the adhesion force, i.e. negative force contact vs. sedimentation and normal-to-substratum retraction vs. tangential detachment conditions, using AFM and flow chamber, respectively. AFM blocking assays with free PGM or O-glycan fractions purified from PGM demonstrated that neutral oligosaccharides played a major role in adhesion of L. lactis TIL448 to PGM. This study dissects L. lactis muco-adhesive phenotype, in relation with the nature of the bacterial surface determinants. PMID:24260308

  7. Synaptic Cell Adhesion Molecules in Alzheimer's Disease

    PubMed Central

    Leshchyns'ka, Iryna

    2016-01-01

    Alzheimer's disease (AD) is a neurodegenerative brain disorder associated with the loss of synapses between neurons in the brain. Synaptic cell adhesion molecules are cell surface glycoproteins which are expressed at the synaptic plasma membranes of neurons. These proteins play key roles in formation and maintenance of synapses and regulation of synaptic plasticity. Genetic studies and biochemical analysis of the human brain tissue, cerebrospinal fluid, and sera from AD patients indicate that levels and function of synaptic cell adhesion molecules are affected in AD. Synaptic cell adhesion molecules interact with Aβ, a peptide accumulating in AD brains, which affects their expression and synaptic localization. Synaptic cell adhesion molecules also regulate the production of Aβ via interaction with the key enzymes involved in Aβ formation. Aβ-dependent changes in synaptic adhesion affect the function and integrity of synapses suggesting that alterations in synaptic adhesion play key roles in the disruption of neuronal networks in AD. PMID:27242933

  8. Fabrication of three-dimensional multi-protein microstructures for cell migration and adhesion enhancement

    PubMed Central

    Da Sie, Yong; Li, Yi-Cheng; Chang, Nan-Shan; Campagnola, Paul J.; Chen, Shean-Jen

    2015-01-01

    In this study, three-dimensional (3D) multi-component microstructures were precisely fabricated via multiphoton excited photochemistry using a femtosecond laser direct-writing system with proposed repetition positioning and vector scanning techniques. Extracellular matrix (ECM) proteins, such as fibronectin (FN), are difficult to stack and form 3D structures larger than several-hundred microns in height due to the nature of their protein structure. Herein, to fabricate complex 3D microstructures with FN, a 3D scaffold was designed and formed from bovine serum albumin (BSA), after which human FN was inserted at specific locations on the BSA scaffold; in this manner, the fabricated ECM microstructure can guide cells in a 3D environment. A human breast cancer cell line, MDA-MB-231, was used to investigate the behavior of cell migration and adhesion on the fabricated human FN and BSA protein structures. Experimental results indicate that many cells are not able to attach or climb on a 3D structure’s inclined plane without FN support; hence, the influence of cell growth in a 3D context with FN should being taken into consideration. This 3D multi-protein fabrication technique holds potential for cell studies in designed complex 3D ECM scaffolds. PMID:25780738

  9. Adhesion and fusion efficiencies of human immunodeficiency virus type 1 (HIV-1) surface proteins

    NASA Astrophysics Data System (ADS)

    Dobrowsky, Terrence M.; Rabi, S. Alireza; Nedellec, Rebecca; Daniels, Brian R.; Mullins, James I.; Mosier, Donald E.; Siliciano, Robert F.; Wirtz, Denis

    2013-10-01

    In about half of patients infected with HIV-1 subtype B, viral populations shift from utilizing the transmembrane protein CCR5 to CXCR4, as well as or instead of CCR5, during late stage progression of the disease. How the relative adhesion efficiency and fusion competency of the viral Env proteins relate to infection during this transition is not well understood. Using a virus-cell fusion assay and live-cell single-molecule force spectroscopy, we compare the entry competency of viral clones to tensile strengths of the individual Env-receptor bonds of Env proteins obtained from a HIV-1 infected patient prior to and during coreceptor switching. The results suggest that the genetic determinants of viral entry were predominantly enriched in the C3, HR1 and CD regions rather than V3. Env proteins can better mediate entry into cells after coreceptor switch; this effective entry capacity does not correlate with the bond strengths between viral Env and cellular receptors.

  10. Simple modifications to Methimazole that enhance its inhibitory effect on Tumor Necrosis Factor-α-induced Vascular Cell Adhesion Molecule-1 expression by human endothelial cells

    PubMed Central

    Alapati, Anuja; Deosarkar, Sudhir P.; Lanier, Olivia L.; Qi, Chunyan; Carlson, Grady E.; Burdick, Monica M.; Schwartz, Frank L.; McCall, Kelly D.; Bergmeier, Stephen C.; Goetz, Douglas J.

    2015-01-01

    The expression of vascular cell adhesion molecule-1 (VCAM-1) on the vascular endothelium can be increased by pro-inflammatory cytokines [e.g. tumor necrosis factor – α (TNF-α)]. VCAM-1 contributes to leukocyte adhesion to, and emigration from, the vasculature which is a key aspect of pathological inflammation. As such, a promising therapeutic approach for pathological inflammation is to inhibit the expression of VCAM-1. Methimazole [3-methyl-1, 3 imidazole-2 thione (MMI)] is routinely used for the treatment of Graves’ disease and patients treated with MMI have decreased levels of circulating VCAM-1. In this study we used cultured human umbilical vein endothelial cells (HUVEC) to investigate the effect of MMI structural modifications on TNF-α induced VCAM-1 expression. We found that addition of a phenyl ring at the 4-nitrogen of MMI yields a compound that is significantly more potent than MMI at inhibiting 24 h TNF-α-induced VCAM-1 protein expression. Addition of a para methoxy to the appended phenyl group increases the inhibition while substitution of a thiazole ring for an imidazole ring in the phenyl derivatives yields no clear difference in inhibition. Addition of the phenyl ring to MMI appears to increase toxicity as does substitution of a thiazole ring for an imidazole ring in the phenyl MMI derivatives. Each of the compounds reduced TNF-α-induced VCAM-1 mRNA expression and had a functional inhibitory effect, i.e. each inhibited monocytic cell adhesion to 24 h TNF-α-activated HUVEC under fluid flow conditions. Combined, these studies provide important insights into the design of MMI-related anti-inflammatory compounds. PMID:25641748

  11. Simple modifications to methimazole that enhance its inhibitory effect on tumor necrosis factor-α-induced vascular cell adhesion molecule-1 expression by human endothelial cells.

    PubMed

    Alapati, Anuja; Deosarkar, Sudhir P; Lanier, Olivia L; Qi, Chunyan; Carlson, Grady E; Burdick, Monica M; Schwartz, Frank L; McCall, Kelly D; Bergmeier, Stephen C; Goetz, Douglas J

    2015-03-15

    The expression of vascular cell adhesion molecule-1 (VCAM-1) on the vascular endothelium can be increased by pro-inflammatory cytokines [e.g. tumor necrosis factor-α (TNF-α)]. VCAM-1 contributes to leukocyte adhesion to, and emigration from, the vasculature which is a key aspect of pathological inflammation. As such, a promising therapeutic approach for pathological inflammation is to inhibit the expression of VCAM-1. Methimazole [3-methyl-1, 3 imidazole-2 thione (MMI)] is routinely used for the treatment of Graves׳ disease and patients treated with MMI have decreased levels of circulating VCAM-1. In this study we used cultured human umbilical vein endothelial cells (HUVEC) to investigate the effect of MMI structural modifications on TNF-α induced VCAM-1 expression. We found that addition of a phenyl ring at the 4-nitrogen of MMI yields a compound that is significantly more potent than MMI at inhibiting 24h TNF-α-induced VCAM-1 protein expression. Addition of a para methoxy to the appended phenyl group increases the inhibition while substitution of a thiazole ring for an imidazole ring in the phenyl derivatives yields no clear difference in inhibition. Addition of the phenyl ring to MMI appears to increase toxicity as does substitution of a thiazole ring for an imidazole ring in the phenyl MMI derivatives. Each of the compounds reduced TNF-α-induced VCAM-1 mRNA expression and had a functional inhibitory effect, i.e. each inhibited monocytic cell adhesion to 24h TNF-α-activated HUVEC under fluid flow conditions. Combined, these studies provide important insights into the design of MMI-related anti-inflammatory compounds.

  12. Focal Adhesion Kinase-mediated Phosphorylation of Beclin1 Protein Suppresses Cardiomyocyte Autophagy and Initiates Hypertrophic Growth*♦

    PubMed Central

    Cheng, Zhaokang; Zhu, Qiang; Dee, Rachel; Opheim, Zachary; Mack, Christopher P.; Cyr, Douglas M.; Taylor, Joan M.

    2017-01-01

    Autophagy is an evolutionarily conserved intracellular degradation/recycling system that is essential for cellular homeostasis but is dysregulated in a number of diseases, including myocardial hypertrophy. Although it is clear that limiting or accelerating autophagic flux can result in pathological cardiac remodeling, the physiological signaling pathways that fine-tune cardiac autophagy are poorly understood. Herein, we demonstrated that stimulation of cardiomyocytes with phenylephrine (PE), a well known hypertrophic agonist, suppresses autophagy and that activation of focal adhesion kinase (FAK) is necessary for PE-stimulated autophagy suppression and subsequent initiation of hypertrophic growth. Mechanistically, we showed that FAK phosphorylates Beclin1, a core autophagy protein, on Tyr-233 and that this post-translational modification limits Beclin1 association with Atg14L and reduces Beclin1-dependent autophagosome formation. Remarkably, although ectopic expression of wild-type Beclin1 promoted cardiomyocyte atrophy, expression of a Y233E phosphomimetic variant of Beclin1 failed to affect cardiomyocyte size. Moreover, genetic depletion of Beclin1 attenuated PE-mediated/FAK-dependent initiation of myocyte hypertrophy in vivo. Collectively, these findings identify FAK as a novel negative regulator of Beclin1-mediated autophagy and indicate that this pathway can facilitate the promotion of compensatory hypertrophic growth. This novel mechanism to limit Beclin1 activity has important implications for treating a variety of pathologies associated with altered autophagic flux. PMID:27994061

  13. AmpA protein functions by different mechanisms to influence early cell type specification and to modulate cell adhesion and actin polymerization in Dictyostelium discoideum.

    PubMed

    Cost, Hoa N; Noratel, Elizabeth F; Blumberg, Daphne D

    2013-01-01

    The Dictyostelium discoideum ampA gene encodes a multifunctional regulator protein that modulates cell-cell and cell-substrate adhesions and actin polymerization during growth and is necessary for correct cell type specification and patterning during development. Insertional inactivation of the ampA gene results in defects that define two distinct roles for the ampA gene during development. AmpA is necessary in a non-cell autonomous manner to prevent premature expression of a prespore gene marker. It is also necessary in a cell autonomous manner for the anterior like cells, which express the ampA gene, to migrate to the upper cup during culmination. It is also necessary to prevent excessive cell-cell agglutination when cells are developed in a submerged suspension culture. Here, we demonstrate that a supernatant source of AmpA protein, added extracellularly, can prevent the premature mis-expression of the prespore marker. Synthetic oligopeptides are used to identify the domain of the AmpA protein that is important for preventing cells from mis-expressing the prespore gene. We further demonstrate that a factor capable of inducing additional cells to express the prespore gene marker accumulates extracellularly in the absence of AmpA protein. While the secreted AmpA acts extracellularly to suppress prespore gene expression, the effects of AmpA on cell agglutination and on actin polymerization in growing cells are not due to an extracellular role of secreted AmpA protein. Rather, these effects appear to reflect a distinct cell autonomous role of the ampA gene. Finally, we show that secretion of AmpA protein is brought about by elevating the levels of expression of ampA so that the protein accumulates to an excessive level.

  14. Rosiglitazone influences the expression of leukocyte adhesion molecules and CD14 receptor in type 2 diabetes mellitus patients.

    PubMed

    Štulc, T; Svobodová, H; Krupičková, Z; Doležalová, R; Marinov, I; Češka, R

    2014-01-01

    Diabetes mellitus is associated with increased inflammatory response, which may contribute to atherosclerosis progression. Experimental results demonstrated anti-inflammatory activity of glitazones; their effect on leukocyte adhesion molecules has not been studied to date. We therefore studied the effect of rosiglitazone treatment on leukocyte surface expression of adhesion molecules in patients with type 2 diabetes mellitus and compared our results with findings in healthy subjects. 33 subjects with type 2 diabetes and 32 healthy controls were included; patients were examined at baseline and after 5 months of rosiglitazone treatment (4 mg/d). Leukocyte expression of adhesion molecules LFA-1, CD18 and ICAM-1 was quantified using flow cytometry; in addition, CD14 (lipopolysaccharide receptor) expression was analyzed as a marker of nonspecific immunity. The expression of examined molecules at baseline was higher in patients compared to controls. Despite only mild decrease in blood glucose, rosiglitazone treatment induced substantial decrease of CD18 and CD14 expression and borderline decrease of LFA-1 and ICAM-1 expression (on monocytes only). We thus observed improvement in the expression of leukocyte inflammatory markers after rosiglitazone treatment. This effect is supposed to be mediated by direct effect of rosiglitazone on PPAR-gamma receptors on leukocytes.

  15. Influence of β2-Integrin Adhesion Molecule Expression and Pulmonary Infection with Pasteurella haemolytica on Cytokine Gene Expression in Cattle

    PubMed Central

    Lee, Haa-Yung; Kehrli, Marcus E.; Brogden, Kim A.; Gallup, Jack M.; Ackermann, Mark R.

    2000-01-01

    β2-Integrins are leukocyte adhesion molecules composed of alpha (CD11a, -b, -c, or -d) and beta (CD18) subunit heterodimers. Genetic CD18 deficiency results in impaired neutrophil egress into tissues that varies between conducting airways and alveoli of the lung. In this study, we investigated whether CD18 deficiency in cattle affects proinflammatory cytokine (PIC) expression in pulmonary tissue after respiratory infection with Pasteurella haemolytica. Cattle were infected with P. haemolytica via fiberoptic deposition of organisms into the posterior part of the right cranial lung lobe. Animals were euthanized at 2 or 4 h postinoculation (p.i.), and tissues were collected to assess PIC gene expression using antisense RNA probes specific for bovine interleukin-1α (IL-1α), IL-1β, IL-6, gamma interferon (IFN-γ), and tumor necrosis factor alpha (TNF-α) along with the β-actin (β-Act) housekeeping gene. Expression of PIC was induced at 2 h p.i. in P. haemolytica-infected cattle and continued to 4 h p.i. At 2 h p.i., induction of gene expression and increase of cells that expressed PIC were observed both in CD18+ and CD18− cattle after inoculation of P. haemolytica. The induction of gene expression with P. haemolytica inoculation was more prominent in CD18− cattle than in CD18+ cattle by comparison to pyrogen-free saline (PFS)-inoculated control animals. At 4 h p.i., however, the induction of PIC, especially IL-1α, IL-6, and IFN-γ, in the lungs of CD18+ cattle inoculated with P. haemolytica was greater than that in lungs of the CD18− cattle. IFN-γ and TNF-α genes were not increased in P. haemolytica-inoculated CD18− cattle lungs compared to the PFS-inoculated control lungs at 4 h p.i. In PFS-inoculated lungs, we generally observed a higher percentage of cells and higher level of gene expression in the lungs of CD18− cattle than in the lungs of CD18+ cattle, especially at 4 h p.i. The rate of neutrophil infiltration into the lungs of CD18− cattle at

  16. Adhesion of mussel foot protein-3 to TiO2 surfaces: the effect of pH.

    PubMed

    Yu, Jing; Wei, Wei; Menyo, Matthew S; Masic, Admir; Waite, J Herbert; Israelachvili, Jacob N

    2013-04-08

    The underwater adhesion of marine mussels relies on mussel foot proteins (mfps) rich in the catecholic amino acid 3,4-dihydroxyphenylalanine (Dopa). As a side chain, Dopa is capable of strong bidentate interactions with a variety of surfaces, including many minerals and metal oxides. Titanium is among the most widely used medical implant material and quickly forms a TiO2 passivation layer under physiological conditions. Understanding the binding mechanism of Dopa to TiO2 surfaces is therefore of considerable theoretical and practical interest. Using a surface forces apparatus, we explored the force-distance profiles and adhesion energies of mussel foot protein 3 (mfp-3) to TiO2 surfaces at three different pHs (pH 3, 5.5 and 7.5). At pH 3, mfp-3 showed the strongest adhesion force on TiO2, with an adhesion energy of ∼-7.0 mJ/m(2). Increasing the pH gives rise to two opposing effects: (1) increased oxidation of Dopa, thus, decreasing availability for the Dopa-mediated adhesion, and (2) increased bidentate Dopa-Ti coordination, leading to the further stabilization of the Dopa group and, thus, an increase in adhesion force. Both effects were reflected in the resonance-enhanced Raman spectra obtained at the three deposition pHs. The two competing effects give rise to a higher adhesion force of mfp-3 on the TiO2 surface at pH 7.5 than at pH 5.5. Our results suggest that Dopa-containing proteins and synthetic polymers have great potential as coating materials for medical implant materials, particularly if redox activity can be controlled.

  17. Cryptosporidium parvum: identification of a new surface adhesion protein on sporozoite and oocyst by screening of a phage-display cDNA library.

    PubMed

    Yao, Longquan; Yin, Jigang; Zhang, Xichen; Liu, Quan; Li, Jianhua; Chen, Lifeng; Zhao, Yueping; Gong, Pengtao; Liu, Chengwu

    2007-04-01

    Cryptosporidium parvum is a significant cause of diarrheal disease worldwide. The specific molecules that mediate C. parvum-host interaction and the molecular mechanisms involved in the pathogenesis are unknown. In this study we described a novel phage display method to identify surface adhesion proteins of C. parvum. A cDNA library of the sporozoite and oocyst stages of C. parvum expressed on the surface of T7 phage was screened with intestinal epithelial cells (IECs) from the newborn Cryptosporidium-free Holstein calves. Proteins that selectively and specifically bound to IECs were then enriched using a multi-step panning procedure. Two proteins of C. parvum were selected, one was previously reported (p23), which was an important surface adhesion protein; the other was a novel surface adherence protein (CP12). Sequence analysis showed that CP12 has a N-terminal signal peptide, a transmembrane region, a N-glycosylation site, a casein kinase II phosphorylation site and two N-myristoylation sites. Immunofluorescence assay (IFA) using antibody specific for rCP12 demonstrated that the antibody can specifically bind the surface of sporozoite and oocyst, especially apical region of sporozoite. The surface localization of CP12 and its involvement in the host-parasite interaction suggest that it may serve as an effective target for specific preventive and therapeutic measures for cryptosporidiosis.

  18. Induction of Fibronectin-Binding Proteins and Increased Adhesion of Quinolone-Resistant Staphylococcus aureus by Subinhibitory Levels of Ciprofloxacin

    PubMed Central

    Bisognano, Carmelo; Vaudaux, Pierre; Rohner, Peter; Lew, Daniel P.; Hooper, David C.

    2000-01-01

    We recently reported that strain EN1252a, a fluoroquinolone-resistant derivative of Staphylococcus aureus NCTC8325 with mutations in grlA and gyrA, expressed increased levels of fibronectin-binding proteins (FnBPs) and showed a significantly higher attachment to fibronectin-coated polymer surfaces after growth in the presence of subinhibitory concentrations of ciprofloxacin. The present study evaluated the occurrence and frequency of fluoroquinolone-induced FnBP-mediated adhesion in clinical isolates of fluoroquinolone-resistant methicillin-resistant S. aureus (MRSA) and methicillin-susceptible S. aureus (MSSA). Eight of ten MRSA isolates and four of six MSSA isolates with grlA and gyrA mutations exhibited significant increases in attachment to fibronectin-coated surfaces after growth in the presence of one-quarter the MIC of ciprofloxacin. Fluoroquinolone-induced FnBP-mediated adhesion of one clinical MRSA strain and the double mutant strain EN1252a also occurred on coverslips removed from the subcutaneous space of guinea pigs. For strain EN1252a, the regulation of fnb transcription by sub-MICs of ciprofloxacin was studied on reporter plasmids carrying fnb-luxAB fusions. One-quarter of the MIC of ciprofloxacin significantly increased fnbB, but not fnbA, promoter activity of the fluoroquinolone-resistant mutant but not its fluoroquinolone-susceptible parent ISP794. This response was abolished by pretreatment with rifampin, indicating an effect at the level of transcription. Activation of the fnbB promoter was not due to an indirect effect of ciprofloxacin on growth rate and still occurred in an agr mutant of strain EN1252a. These data suggest that sub-MIC levels of ciprofloxacin activate the fnbB promoter of some laboratory and clinical isolates, thus contributing to increased production of FnBP(s) and leading to higher levels of bacterial attachment to fibronectin-coated or subcutaneously implanted coverslips. PMID:10817688

  19. Expression of beta 1B integrin isoform in CHO cells results in a dominant negative effect on cell adhesion and motility

    PubMed Central

    1994-01-01

    The integrin subunit beta 1B, a beta 1 isoform with a unique sequence at the cytoplasmic domain, forms heterodimers with integrin alpha chains and binds fibronectin, but it does not localize to focal adhesion sites (Balzac, F., A. Belkin, V. Koteliansky, Y. Balabanow, F. Altruda, L. Silengo, and G. Tarone. 1993. J. Cell Biol. 121:171-178). Here we analyze the functional properties of human beta 1B by expressing it in hamster CHO cells. When stimulated by specific antibodies, beta 1B does not trigger tyrosine phosphorylation of a 125- kD cytosolic protein, an intracellular signalling pathway that is activated both by the endogenous hamster or the transfected human beta 1A. Moreover, expression of beta 1B results in reduced spreading on fibronectin and laminin, but not on vitronectin. Expression of beta 1B also results in severe reduction of cell motility in the Boyden chamber assay. Reduced cell spreading and motility could not be accounted for by preferential association of beta 1B with a given integrin alpha subunit. These data, together with our previous results, indicate that beta 1B interferes with beta 1A function when expressed in CHO cells resulting in a dominant negative effect on cell adhesion and migration. PMID:7523423

  20. Expression of beta 1B integrin isoform in CHO cells results in a dominant negative effect on cell adhesion and motility.

    PubMed

    Balzac, F; Retta, S F; Albini, A; Melchiorri, A; Koteliansky, V E; Geuna, M; Silengo, L; Tarone, G

    1994-10-01

    The integrin subunit beta 1B, a beta 1 isoform with a unique sequence at the cytoplasmic domain, forms heterodimers with integrin alpha chains and binds fibronectin, but it does not localize to focal adhesion sites (Balzac, F., A. Belkin, V. Koteliansky, Y. Balabanow, F. Altruda, L. Silengo, and G. Tarone. 1993. J. Cell Biol. 121:171-178). Here we analyze the functional properties of human beta 1B by expressing it in hamster CHO cells. When stimulated by specific antibodies, beta 1B does not trigger tyrosine phosphorylation of a 125-kD cytosolic protein, an intracellular signalling pathway that is activated both by the endogenous hamster or the transfected human beta 1A. Moreover, expression of beta 1B results in reduced spreading on fibronectin and laminin, but not on vitronectin. Expression of beta 1B also results in severe reduction of cell motility in the Boyden chamber assay. Reduced cell spreading and motility could not be accounted for by preferential association of beta 1B with a given integrin alpha subunit. These data, together with our previous results, indicate that beta 1B interferes with beta 1A function when expressed in CHO cells resulting in a dominant negative effect on cell adhesion and migration.

  1. Investigation of alginate binding to germanium and polystyrene substrata conditioned with mussel adhesive protein

    SciTech Connect

    Suci, P.A.; Geesey, G.G.

    1995-06-15

    Binding of alginate from Macrocystis pyrifera (kelp) to germanium and polystyrene substrata conditioned with mussel adhesive protein (MAP) from Mytilis edulis, to germanium substrata conditioned with bovine serum albumin (BSA) and polylysine, and to germanium substrata coated with aminopropyltriethoxysilane (APS) was investigated using attenuated total reflection Fourier transform infrared spectrometry. Binding of alginate to MAP appears to be proportional to surface coverage for levels tested. Distinct spectral features appear in the region associated with pyranose ring vibrations upon binding of alginate to MAP, polylysine, and APS, indicating that lysine residues play a prominent role in promoting irreversible adsorption with perturbation of pyranose ring atoms. BSA does not appear to enhance alginate adsorption over that observed on clean germanium and no new spectral features appear as a result of binding. The level of irreversible binding of alginate to germanium and polystyrene substrata conditioned with MAP is similar.

  2. Novel pyridazinone inhibitors for vascular adhesion protein-1 (VAP-1): old target-new inhibition mode.

    PubMed

    Bligt-Lindén, Eva; Pihlavisto, Marjo; Szatmári, István; Otwinowski, Zbyszek; Smith, David J; Lázár, László; Fülöp, Ferenc; Salminen, Tiina A

    2013-12-27

    Vascular adhesion protein-1 (VAP-1) is a primary amine oxidase and a drug target for inflammatory and vascular diseases. Despite extensive attempts to develop potent, specific, and reversible inhibitors of its enzyme activity, the task has proven challenging. Here we report the synthesis, inhibitory activity, and molecular binding mode of novel pyridazinone inhibitors, which show specificity for VAP-1 over monoamine and diamine oxidases. The crystal structures of three inhibitor-VAP-1 complexes show that these compounds bind reversibly into a unique binding site in the active site channel. Although they are good inhibitors of human VAP-1, they do not inhibit rodent VAP-1 well. To investigate this further, we used homology modeling and structural comparison to identify amino acid differences, which explain the species-specific binding properties. Our results prove the potency and specificity of these new inhibitors, and the detailed characterization of their binding mode is of importance for further development of VAP-1 inhibitors.

  3. Development of robust biocompatible silicone with high resistance to protein adsorption and bacterial adhesion.

    PubMed

    Lin, Weifeng; Zhang, Juan; Wang, Zhen; Chen, Shengfu

    2011-05-01

    A new biocompatible silicone comprising a carboxybetaine (CB) ester analogue, 3-methacryloxypropyltris(trimethylsiloxy)silane (TRIS) and an organic silicone macromer (bis-α,ω-(methacryloxypropyl) polydimethylsiloxane) has been developed using photo-polymerisation. Following interfacial hydrolysis of the CB ester, the resulting zwitterionic material became significantly more hydrophilic and exhibited high resistance to both non-specific protein adsorption and bacterial adhesion. Moreover, the stability of these non-fouling properties was dramatically improved by using a slow and controlled rate of ester hydrolysis of the original protective hydrophobic matrix. The subsequent ability to maintain the original optical and mechanical properties of the bare silicone following surface activation makes this material an ideal candidate for preparing contact lenses and other medical devices.

  4. Novel Pyridazinone Inhibitors for Vascular Adhesion Protein-1 (VAP-1): Old target – New Inhibition Mode

    PubMed Central

    Bligt-Lindén, Eva; Pihlavisto, Marjo; Szatmári, István; Otwinowski, Zbyszek; Smith, David J.; Lázár, László; Fülöp, Ferenc; Salminen, Tiina A.

    2014-01-01

    Vascular adhesion protein-1 (VAP-1) is a primary amine oxidase and a drug target for inflammatory and vascular diseases. Despite extensive attempts to develop potent, specific and reversible inhibitors of its enzyme activity, the task has proven challenging. Here we report the synthesis, inhibitory activity and molecular binding mode of novel pyridazinone inhibitors, which show specificity for VAP-1 over monoamine and diamine oxidases. The crystal structures of three inhibitor-VAP-1 complexes show that these compounds bind reversibly into a unique binding site in the active site channel. Though they are good inhibitors of human VAP-1, they do not inhibit rodent VAP-1 well. To investigate this further, we used homology modeling and structural comparison to identify amino acid differences, which explain the species-specific binding properties. Our results prove the potency and specificity of these new inhibitors and the detailed characterization of their binding mode is of importance for further development of VAP-1 inhibitors. PMID:24304424

  5. Bioinspired Universal Monolayer Coatings by Combining Concepts from Blood Protein Adsorption and Mussel Adhesion.

    PubMed

    Yu, Leixiao; Cheng, Chong; Ran, Qidi; Schlaich, Christoph; Noeske, Paul-Ludwig Michael; Li, Wenzhong; Wei, Qiang; Haag, Rainer

    2017-02-22

    Despite the increasing need for universal polymer coating strategies, only a few approaches have been successfully developed, and most of them are suffering from color, high thickness, or high roughness. In this paper, we present for the first time a universal monolayer coating that is only a few nanometers thick and independent of the composition, size, shape, and structure of the substrate. The coating is based on a bioinspired synthetic amphiphilic block copolymer that combines two concepts from blood protein adsorption and mussel adhesion. This polymer can be rapidly tethered on various substrates including both planar surfaces and nanosystems with high grafting density. The resulting monolayer coatings are, on the one hand, inert to the adsorption of multiple polymer layers and prevent biofouling. On the other hand, they are chemically active for secondary functionalization and provide a new platform for selective material surface modification.

  6. Streamlined expressed protein ligation using split inteins.

    PubMed

    Vila-Perelló, Miquel; Liu, Zhihua; Shah, Neel H; Willis, John A; Idoyaga, Juliana; Muir, Tom W

    2013-01-09

    Chemically modified proteins are invaluable tools for studying the molecular details of biological processes, and they also hold great potential as new therapeutic agents. Several methods have been developed for the site-specific modification of proteins, one of the most widely used being expressed protein ligation (EPL) in which a recombinant α-thioester is ligated to an N-terminal Cys-containing peptide. Despite the widespread use of EPL, the generation and isolation of the required recombinant protein α-thioesters remain challenging. We describe here a new method for the preparation and purification of recombinant protein α-thioesters using engineered versions of naturally split DnaE inteins. This family of autoprocessing enzymes is closely related to the inteins currently used for protein α-thioester generation, but they feature faster kinetics and are split into two inactive polypeptides that need to associate to become active. Taking advantage of the strong affinity between the two split intein fragments, we devised a streamlined procedure for the purification and generation of protein α-thioesters from cell lysates and applied this strategy for the semisynthesis of a variety of proteins including an acetylated histone and a site-specifically modified monoclonal antibody.

  7. Link protein hyaluronan-binding motif abrogates CD44-hyaluronan-mediated leukemia-liver cell adhesion.

    PubMed

    Chen, Jing; Li, Na; Li, Gongchu

    2013-05-01

    The liver is a frequent site for the metastasis of cancer cells originating from other sites. Leukemic liver metastasis is associated with poor prognosis. The ligation of CD44 with hyaluronan (HA) has been shown to contribute to the drug resistance of leukemic cells. In this study, a link protein HA-binding motif was genetically fused with enhanced green fluorescence protein (EGFP) to generate an EGFP-L fusion protein. Furthermore, a coculture system was established to investigate the interaction of leukemic cells with liver cells. CD44-positive Kasumi-1, but not CD44-negative HL-60 cells, were observed to adhere to the liver cell line L02. This cell-cell adhesion was significantly blocked by HA, indicating that Kasumi-L02 cell adhesion was mediated by the CD44-HA interaction. Compared to EGFP, EGFP-L fusion protein bound to L02 and BEL7404 liver cells. EGFP-L partially abrogated the Kasumi-L02 adhesion, suggesting that the link protein-binding motif is able to inhibit CD44-HA-mediated leukemia-liver adhesion. These results may help provide insight into novel therapeutic methods for leukemic patients diagnosed with liver metastasis.

  8. Expression and Function of C/EBP Homology Protein (GADD153) in Podocytes

    PubMed Central

    Bek, Martin F.; Bayer, Michael; Müller, Barbara; Greiber, Stefan; Lang, Detlef; Schwab, Albrecht; August, Christian; Springer, Erik; Rohrbach, Rolf; Huber, Tobias B.; Benzing, Thomas; Pavenstädt, Hermann

    2006-01-01

    Podocytes are crucial for the permeability of the glomerular filtration barrier. In glomerular disease, however, reactive oxygen species (ROS) may be involved in podocyte injury and subsequent proteinuria. Here, we describe ROS-dependent gene induction in differentiated podocytes stimulated with H2O2 or xanthine/xanthine-oxidase. Superoxide anions and H2O2 increased mRNA and protein expression of GAS5 (growth arrest-specific protein 5) and CHOP (C/EBP homology protein). Cultured podocytes overexpressing CHOP showed increased generation of superoxide anions compared to controls. In addition, the expression of α3/β1 integrins, crucial for cell-matrix interaction of podocytes, was down-regulated, leading to increased cell-matrix adhesion and cell displacement. The altered cell-matrix adhesion was antagonized by the ROS scavenger 1,3-dimethyl-2-thiourea, and the increase in cell displacement could be mimicked by stimulating untransfected podocytes with puromycin, an inductor of ROS. We next performed immunohistochemical staining of human kidney tissue (normal, membranous nephropathy, focal segmental glomerulosclerosis, and minimal change nephropathy) as well as sections from rats with puromycin nephrosis, a model of minimal change nephropathy. CHOP was weakly expressed in podocytes of control kidneys but up-regulated in most proteinuric human kidneys and in rat puromycin nephrosis. Our data suggest that CHOP—via increased ROS generation—regulates cell-matrix adhesion of podocytes in glomerular disease. PMID:16400006

  9. PBRM1 Regulates the Expression of Genes Involved in Metabolism and Cell Adhesion in Renal Clear Cell Carcinoma

    PubMed Central

    Chowdhury, Basudev; Porter, Elizabeth G.; Stewart, Jane C.; Ferreira, Christina R.; Schipma, Matthew J.; Dykhuizen, Emily C.

    2016-01-01

    Polybromo-1 (PBRM1) is a component of the PBAF (Polybromo-associated-BRG1- or BRM-associated factors) chromatin remodeling complex and is the second most frequently mutated gene in clear-cell renal cell Carcinoma (ccRCC). Mutation of PBRM1 is believed to be an early event in carcinogenesis, however its function as a tumor suppressor is not understood. In this study, we have employed Next Generation Sequencing to profile the differentially expressed genes upon PBRM1 re-expression in a cellular model of ccRCC. PBRM1 re-expression led to upregulation of genes involved in cellular adhesion, carbohydrate metabolism, apoptotic process and response to hypoxia, and a downregulation of genes involved in different stages of cell division. The decrease in cellular proliferation upon PBRM1 re-expression was confirmed, validating the functional role of PBRM1 as a tumor suppressor in a cell-based model. In addition, we identified a role for PBRM1 in regulating metabolic pathways known to be important for driving ccRCC, including the regulation of hypoxia response genes, PI3K signaling, glucose uptake, and cholesterol homeostasis. Of particular novelty is the identification of cell adhesion as a major downstream process uniquely regulated by PBRM1 expression. Cytoskeletal reorganization was induced upon PBRM1 reexpression as evidenced from the increase in the number of cells displaying cortical actin, a hallmark of epithelial cells. Genes involved in cell adhesion featured prominently in our transcriptional dataset and overlapped with genes uniquely regulated by PBRM1 in clinical specimens of ccRCC. Genes involved in cell adhesion serve as tumor suppressor and maybe involved in inhibiting cell migration. Here we report for the first time genes linked to cell adhesion serve as downstream targets of PBRM1, and hope to lay the foundation of future studies focusing on the role of chromatin remodelers in bringing about these alterations during malignancies. PMID:27100670

  10. Exported proteins in probiotic bacteria: adhesion to intestinal surfaces, host immunomodulation and molecular cross-talking with the host.

    PubMed

    Sánchez, Borja; Bressollier, Philippe; Urdaci, María C

    2008-10-01

    The group of exported proteins of a bacterium are those proteins that are sorted from the cytoplasm to the bacterial surface or to the surroundings of the microorganism. In probiotic bacteria, these proteins are of special relevance because they might determine important traits such as adhesion to intestinal surfaces and molecular cross-talking with the host. Current knowledge about the presence and biological relevance of exported proteins produced by the main genera of probiotic bacteria in the gastrointestinal environment is reviewed in this minireview. As will be seen, some of these proteins are involved in host adhesion or are able to modify certain signalization pathways within host cells, whereas others are important for the physiology of probiotic bacteria in the gastrointestinal tract.

  11. Adhesive Properties of YapV and Paralogous Autotransporter Proteins of Yersinia pestis

    PubMed Central

    Nair, Manoj K. M.; De Masi, Leon; Yue, Min; Galván, Estela M.; Chen, Huaiqing; Wang, Fang

    2015-01-01

    Yersinia pestis is the causative agent of plague. This bacterium evolved from an ancestral enteroinvasive Yersinia pseudotuberculosis strain by gene loss and acquisition of new genes, allowing it to use fleas as transmission vectors. Infection frequently leads to a rapidly lethal outcome in humans, a variety of rodents, and cats. This study focuses on the Y. pestis KIM yapV gene and its product, recognized as an autotransporter protein by its typical sequence, outer membrane localization, and amino-terminal surface exposure. Comparison of Yersinia genomes revealed that DNA encoding YapV or each of three individual paralogous proteins (YapK, YapJ, and YapX) was present as a gene or pseudogene in a strain-specific manner and only in Y. pestis and Y. pseudotuberculosis. YapV acted as an adhesin for alveolar epithelial cells and specific extracellular matrix (ECM) proteins, as shown with recombinant Escherichia coli, Y. pestis, or purified passenger domains. Like YapV, YapK and YapJ demonstrated adhesive properties, suggesting that their previously related in vivo activity is due to their capacity to modulate binding properties of Y. pestis in its hosts, in conjunction with other adhesins. A differential host-specific type of binding to ECM proteins by YapV, YapK, and YapJ suggested that these proteins participate in broadening the host range of Y. pestis. A phylogenic tree including 36 Y. pestis strains highlighted an association between the gene profile for the four paralogous proteins and the geographic location of the corresponding isolated strains, suggesting an evolutionary adaption of Y. pestis to specific local animal hosts or reservoirs. PMID:25690102

  12. Effect of anticoagulants on the protein corona-induced reduced drug carrier adhesion efficiency in human blood flow.

    PubMed

    Sobczynski, Daniel J; Eniola-Adefeso, Omolola

    2017-01-15

    Plasma proteins rapidly coat the surfaces of particulate drug carriers to form a protein corona upon their injection into the bloodstream. The high presence of immunoglobulins in the corona formed on poly(lactic-co-glycolic acid) (PLGA) vascular-targeted carrier (VTC) surfaces was recently shown to negatively impact their adhesion to activated endothelial cells (aECs) in vitro. Here, we characterized the influence of anticoagulants, or their absence, on the binding efficiency of VTCs of various materials via modulation of their protein corona. Specifically, we evaluated the adhesion of PLGA, poly(lactic acid) (PLA), polycaprolactone (PCL), silica, and polystyrene VTCs to aECs in heparinized, citrated, and non-anticoagulated (serum and whole) blood flows relative to buffer control. Particle adhesion is substantially reduced in non-anticoagulated blood flows regardless of the material type while only moderate to minimal reduction is observed for VTCs in anticoagulant-containing blood flow depending on the anticoagulant and material type. The substantial reduction in VTC adhesion in blood flows was linked to a high presence of immunoglobulin-sized proteins in the VTC corona via SDS-PAGE analysis. Of all the materials evaluated, PLGA was the most sensitive to plasma protein effects while PCL was the most resistant, suggesting particle hydrophobicity is a critical component of the observed negative plasma protein effects. Overall, this work demonstrates that anticoagulant positively alters the effect of plasma proteins in prescribing VTC adhesion to aECs in human blood flow, which has implication in the use of in vitro blood flow assays for functional evaluation of VTCs for in vivo use.

  13. Lipopolysaccharide induces VCAM-1 expression and neutrophil adhesion to human tracheal smooth muscle cells: Involvement of Src/EGFR/PI3-K/Akt pathway

    SciTech Connect

    Lin, W.-N.; Luo, S.-F.; Wu, C.-B.; Lin, C.-C.; Yang, C.-M.

    2008-04-15

    In our previous study, LPS has been shown to induce vascular cell adhesion molecule-1(VCAM-1) expression through MAPKs and NF-{kappa}B in human tracheal smooth muscle cells (HTSMCs). In addition to these pathways, the non-receptor tyrosine kinases (Src), EGF receptor (EGFR), and phosphatidylinositol 3-kinase (PI3K) have been shown to be implicated in the expression of several inflammatory target proteins. Here, we reported that LPS-induced up-regulation of VCAM-1 enhanced the adhesion of neutrophils onto HTSMC monolayer, which was inhibited by LY294002 and wortmannin. LPS stimulated phosphorylation of protein tyrosine kinases including Src, PYK2, and EGFR, which were further confirmed using specific anti-phospho-Src, PYK2, or EGFR Ab, respectively, revealed by Western blotting. LPS-stimulated Src, PYK2, EGFR, and Akt phosphorylation and VCAM-1 expression were attenuated by the inhibitors of Src (PP1), EGFR (AG1478), PI3-K (LY294002 and wortmannin), and Akt (SH-5), respectively, or transfection with siRNAs of Src or Akt and shRNA of p110. LPS-induced VCAM-1 expression was also blocked by pretreatment with curcumin (a p300 inhibitor) or transfection with p300 siRNA. LPS-stimulated Akt activation translocated into nucleus and associated with p300 and VCAM-1 promoter region was further confirmed by immunofluorescence, immunoprecipitation, and chromatin immunoprecipitation assays. This association of Akt and p300 to VCAM-1 promoter was inhibited by pretreatment with PP1, AG1478, wortmannin, and SH-5. LPS-induced p300 activation enhanced VCAM-1 promoter activity and VCAM-1 mRNA expression. These results suggested that in HTSMCs, Akt phosphorylation mediated through transactivation of Src/PYK2/EGFR promoted the transcriptional p300 activity and eventually led to VCAM-1 expression induced by LPS.

  14. kakapo, a gene required for adhesion between and within cell layers in Drosophila, encodes a large cytoskeletal linker protein related to plectin and dystrophin.

    PubMed

    Gregory, S L; Brown, N H

    1998-11-30

    Mutations in kakapo were recovered in genetic screens designed to isolate genes required for integrin-mediated adhesion in Drosophila. We cloned the gene and found that it encodes a large protein (>5,000 amino acids) that is highly similar to plectin and BPAG1 over the first 1,000-amino acid region, and contains within this region an alpha-actinin type actin-binding domain. A central region containing dystrophin-like repeats is followed by a carboxy domain that is distinct from plectin and dystrophin, having neither the intermediate filament-binding domain of plectin nor the dystroglycan/syntrophin-binding domain of dystrophin. Instead, Kakapo has a carboxy terminus similar to the growth arrest-specific protein Gas2. Kakapo is strongly expressed late during embryogenesis at the most prominent site of position-specific integrin adhesion, the muscle attachment sites. It is concentrated at apical and basal surfaces of epidermal muscle attachment cells, at the termini of the prominent microtubule bundles, and is required in these cells for strong attachment to muscles. Kakapo is also expressed more widely at a lower level where it is essential for epidermal cell layer stability. These results suggest that the Kakapo protein forms essential links among integrins, actin, and microtubules.

  15. Glycosylation Genes Expressed in Seam Cells Determine Complex Surface Properties and Bacterial Adhesion to the Cuticle of Caenorhabditis elegans

    PubMed Central

    Gravato-Nobre, Maria J.; Stroud, Dave; O'Rourke, Delia; Darby, Creg; Hodgkin, Jonathan

    2011-01-01

    The surface of the nematode Caenorhabditis elegans is poorly understood but critical for its interactions with the environment and with pathogens. We show here that six genes (bus-2, bus-4, and bus-12, together with the previously cloned srf-3, bus-8, and bus-17) encode proteins predicted to act in surface glycosylation, thereby affecting disease susceptibility, locomotory competence, and sexual recognition. Mutations in all six genes cause resistance to the bacterial pathogen Microbacterium nematophilum, and most of these mutations also affect bacterial adhesion and biofilm formation by Yersinia species, demonstrating that both infection and biofilm formation depend on interaction with complex surface carbohydrates. A new bacterial interaction, involving locomotory inhibition by a strain of Bacillus pumilus, reveals diversity in the surface properties of these mutants. Another biological property—contact recognition of hermaphrodites by males during mating—was also found to be impaired in mutants of all six genes. An important common feature is that all are expressed most strongly in seam cells, rather than in the main hypodermal syncytium, indicating that seam cells play the major role in secreting surface coat and consequently in determining environmental interactions. To test for possible redundancies in gene action, the 15 double mutants for this set of genes were constructed and examined, but no synthetic phenotypes were observed. Comparison of the six genes shows that each has distinctive properties, suggesting that they do not act in a linear pathway. PMID:20980242

  16. Characterization of the porcine sperm adhesion molecule gene SPAM1- expression analysis, genomic structure, and chromosomal mapping.

    PubMed

    Day, A E; Quilter, C R; Sargent, C A; Mileham, A J

    2002-06-01

    Sequence analysis of cDNA products, derived from adult porcine testis mRNA, gave overlapping nucleotide sequence correlating to 1952 bp of the sperm adhesion molecule 1 (SPAM1) gene. This sequence was shown to be homologous to SPAM1 genes known in other mammalian species and contained an open reading frame encoding a 493-amino acid protein. Fluorescence in situ hybridization (FISH), using a bacterial artificial chromosome (BAC) clone from the PigE BAC library, was used to map SPAM1 to chromosome 18 of the pig. This finding is consistent with comparative mapping experiments performed between pig and human chromosomes. Polymerase chain reaction (PCR) analysis of genomic DNA has shown that the 1952 bp of cDNA sequence spans approximately 9 kb of genomic DNA and comprises of at least four exons, with its size and structure being relatively conserved between mouse, human and pig. Reverse transcriptase (RT)-PCR analysis of mRNA from nine porcine tissues has also suggested that expression of SPAM1 is limited to the testis.

  17. Effect of dispersion method and CNT loading on the quality and performance of nanocomposite soy protein/CNTs adhesive for wood application

    NASA Astrophysics Data System (ADS)

    Afolabi, Ayo Samuel; Oluwafolakemi Sadare, Olawumi; Olawale Daramola, Michael

    2016-09-01

    In this article the effect of dispersion method and carbon nanotubes (CNTs) loading on the quality and performance of a nanocomposite adhesive is reported. The nanocomposite soy protein isolate adhesive was successfully developed by incorporating CNTs into the soy protein isolate (SPI) for enhanced bond strength and water resistance. Dispersion methods, namely mechanical (shear) mixing and mechanical/sonication were employed to aid good dispersion and interfacial interaction between soy protein matrix and the carbon nanofillers during the preparation of the adhesive. The concentration of the CNT was varied from 0.1-0.7 wt% in the nanocomposite adhesive. The morphology and the surface chemistry of the adhesives were checked with SEM and FTIR, respectively. The shear strength of the developed adhesives was investigated according to European standard (EN-204) for interior wood application on a tensile testing machine. The morphological structure of the nanocomposite adhesive obtained from SEM images showed homogeneous dispersion of CNTs in SPI using the two dispersion methods; shear mixing and sonication/shear mixing. Fourier transform infrared spectra showed chemical functionalities and successful interaction between CNTs and SPI adhesive. Thermogravimetric profile of the adhesive samples showed that the newly developed nanocomposite adhesive was thermally stable at a temperature up to about 600 °C at a higher percentage loading of 0.5 wt% CNTs. The result showed that sonication method of dispersion of CNTs into the SPI adhesive had a higher shear strength compared to the mechanical method of dispersion both at dry and wet state.

  18. Nanoscale organization of synaptic adhesion proteins revealed by single-molecule localization microscopy.

    PubMed

    Chamma, Ingrid; Levet, Florian; Sibarita, Jean-Baptiste; Sainlos, Matthieu; Thoumine, Olivier

    2016-10-01

    The advent of superresolution imaging has created a strong need for both optimized labeling strategies and analysis methods to probe the nanoscale organization of complex biological structures. We present a thorough description of the distribution of synaptic adhesion proteins at the nanoscopic scale, namely presynaptic neurexin-[Formula: see text] ([Formula: see text]), and its two postsynaptic binding partners neuroligin-1 (Nlg1) and leucine-rich-repeat transmembrane protein 2 (LRRTM2). We monitored these proteins in the membrane of neurons by direct stochastic optical reconstruction microscopy, after live surface labeling with Alexa647-conjugated monomeric streptavidin. The small probe ([Formula: see text]) efficiently penetrates into crowded synaptic junctions and reduces the distance to target. We quantified the organization of the single-molecule localization data using a tesselation-based analysis technique. We show that Nlg1 exhibits a fairly disperse organization within dendritic spines, while LRRTM2 is organized in compact domains, and [Formula: see text] in presynaptic terminals displays a dual-organization pattern intermediate between that of Nlg1 and LRRTM2. These results suggest that part of [Formula: see text] interacts transsynaptically with Nlg1 and the other part with LRRTM2.

  19. Medium-density particleboards from modified rice husks and soybean protein concentrate-based adhesives.

    PubMed

    Ciannamea, Emiliano M; Stefani, Pablo M; Ruseckaite, Roxana A

    2010-01-01

    The main goal of this work was to evaluate the technical feasibility of using rice husk (RH) as wood substitute in the production of environmentally sound medium-density particleboards using adhesives from soybean protein concentrate (SPC). Chemical modification of rice husk with sodium hydroxide and sodium hydroxide followed by hydrogen peroxide (bleaching) were undertaken to evaluate the effect of such treatments on the composition and topology of rice husk and the performance of produced panels. Both treatments were efficient in partially eliminating hemicelluloses, lignin and silica from RH, as evidenced by thermo-gravimetric analysis (TGA). Scanning electron microscopy observations suggested that alkaline treatment resulted in a more damaged RH substrate than bleaching. The dependence of mechanical properties (modulus of rupture, modulus of elasticity, and internal bond) and the physical properties (water absorption and thickness swelling) on chemical treatments performed on both, rice husk and SPC was studied. Bleached-rice husk particleboards bonded with alkaline-treated soybean protein concentrate displayed the best set of final properties. Particleboards with this formulation met the minimum requirements of internal bond, modulus of elasticity and modulus of rupture recommended by the US Standard ANSI/A208.1 specifications for M1, MS and M2-grade medium-density particleboards, but failed to achieve the thickness swelling value recommended for general use panels. This limitation of soybean protein concentrate-bonded rice husk particleboards was counterbalanced by the advantage of being formaldehyde-free which makes them a suitable alternative for indoor applications.

  20. Catechol-functionalized adhesive polymer nanoparticles for controlled local release of bone morphogenetic protein-2 from titanium surface.

    PubMed

    Lee, Hong Jae; Koo, Ahn Na; Lee, Suk Won; Lee, Myung Hyun; Lee, Sang Cheon

    2013-09-10

    We report on a novel surface functionalization approach to equip the titanium (Ti) surfaces with osteogenic properties. A key feature of the approach is the treatment of the Ti surfaces with Ti-adhesive nanoparticles that can stably load and controllably release bone morphogenetic protein-2 (BMP-2). Ti-adhesive nanoparticles were prepared by self-assembly of a catechol-functionalized poly(amino acid) diblock copolymer, catechol-poly(L-aspartic acid)-b-poly(L-phenylalanine) (Cat-PAsp-PPhe). The nanoparticles consist of Ti-adhesive peripheral catechol groups, anionic PAsp shells, and PPhe inner cores. Field-emission scanning electron microscopy (Fe-SEM) images showed that the Ti-adhesive nanoparticles could be uniformly immobilized on Ti surfaces. X-ray photoelectron spectroscopy (XPS) confirmed the successful anchoring of nanoparticles onto Ti surfaces. After surface immobilization of the nanoparticles, the static water contact angle of the Ti substrate decreased from 75.3° to 50.0° or 36.4°, depending on the surface nanoparticle. Fluorescence microscopic analysis showed that BMP-2 could be effectively incorporated onto the Ti surface with adhesive nanoparticles. BMP-2 was controllably released for up to 40 days. The Ti substrate functionalized with BMP-2-incorporated nanoparticles significantly promoted attachment, proliferation, spreading, and alkaline phosphatase (ALP) activity of human adipose-derived stem cell (hADSC). The catechol-functionalized adhesive nanoparticles may be applied to various medical devices to create surfaces for improved performance.

  1. Oncostatin M is a proinflammatory mediator. In vivo effects correlate with endothelial cell expression of inflammatory cytokines and adhesion molecules.

    PubMed Central

    Modur, V; Feldhaus, M J; Weyrich, A S; Jicha, D L; Prescott, S M; Zimmerman, G A; McIntyre, T M

    1997-01-01

    Oncostatin M is a member of the IL-6 family of cytokines that is primarily known for its effects on cell growth. Endothelial cells have an abundance of receptors for oncostatin M, and may be its primary target. We determined if oncostatin M induces a key endothelial cell function, initiation of the inflammatory response. We found that subcutaneous injection of oncostatin M in mice caused an acute inflammatory reaction. Oncostatin M in vitro stimulated: (a) polymorphonuclear leukocyte (PMN) transmigration through confluent monolayers of primary human endothelial cells; (b) biphasic PMN adhesion through rapid P-selectin expression, and delayed adhesion mediated by E-selectin synthesis; (c) intercellular adhesion molecule-1 and vascular cell adhesion molecule-1 accumulation; and (d) the expression of PMN activators IL-6, epithelial neutrophil activating peptide-78, growth-related cytokine alpha and growth-related cytokine beta without concomitant IL-8 synthesis. The nature of the response to oncostatin M varied with concentration, suggesting high and low affinity oncostatin M receptors independently stimulated specific responses. Immunohistochemistry showed that macrophage-like cells infiltrating human aortic aneurysms expressed oncostatin M, so it is present during a chronic inflammatory reaction. Therefore, oncostatin M, but not other IL-6 family members, fulfills Koch's postulates as an inflammatory mediator. Since its effects on endothelial cells differ significantly from established mediators like TNFalpha, it may uniquely contribute to the inflammatory cycle. PMID:9202068

  2. [Effects of crocetin on VCAM-1 expression in human umbilical vein endothelial cells and monocyte-endothelial cell adhesion].

    PubMed

    Zheng, Shu-guo; Zhao, Meng-qiu; Ren, You-nan; Yang, Jie-ren; Qian, Zhi-yu

    2015-01-01

    Crocetin, a naturally occurring carotenoid, possesses antioxidant and antiatherosclerotic properties, of which the underlying mechanism remains unclear. In the present study, we examined the effects of crocetin (0.1, 1, 10 μmol·L(-1)) on angiotensin II (Ang II, 0.1 μmol·L(-1)) induced expression of vascular cell adhesion molecule-1 (VCAM-1) in human umbilical vein endothelial cells (HUVECs) and monocyte-endothelial cell adhesion. The effects of crocetin on the activation of nuclear factor kappa B (NF-κB) and intracellular reactive oxygen species (ROS) were also observed. The results demonstrated that crocetin notably suppressed Ang II induced NF-κB activation (P<0.01) and VCAM-1 expression (P<0.05, P<0.01) in HUVECs, accompanied by a markedly reduced monocyte-endothelial cell adhesion (P<0.05, P<0.01). In addition, preincubation with crocetin resulted in a significant enhancement of cellular antioxidant capacity (P<0.05, P<0.01), while Ang II induced intracellular ROS decreased markedly (P<0.05, P<0.01). These results indicated that crocetin was capable of suppressing Ang II induced VCAM-1 expression and monocyte-endothelial cell adhesion by suppression of NF-κB activation, which might be derived from the enhancement of antioxidant capacity and subsequent reduction of intracellular ROS.

  3. Laminin-511: a multi-functional adhesion protein regulating cell migration, tumor invasion and metastasis.

    PubMed

    Pouliot, Normand; Kusuma, Nicole

    2013-01-01

    Laminins are major constituents of basement membranes. At least 16 isoforms have now been described, each with distinct spatio-temporal expression patterns and functions. The laminin-511 heterotrimer (α5β1γ1) is one of the more recent isoforms to be identified and a potent adhesive and pro-migratory substrate for a variety of normal and tumor cell lines in vitro. As our understanding of its precise function in normal tissues and in pathologies is rapidly unraveling, current evidence suggests an important regulatory role in cancer. This review describes published data on laminin-511 expression in several malignancies and experimental evidence from both in vitro and in vivo studies supporting its functional role during tumor progression. A particular emphasis is put on more recent studies from our laboratory and that of others indicating that laminin-511 contributes to tumor dissemination and metastasis in advanced breast carcinomas and other tumor types. Collectively, the experimental evidence suggests that high expression of laminin-511 has prognostic significance and that targeting tumor-laminin-511 interactions may have therapeutic potential in advanced cancer patients.

  4. A protein interaction map for cell-cell adhesion regulators identifies DUSP23 as a novel phosphatase for β-catenin

    PubMed Central

    Gallegos, Lisa Leon; Ng, Mei Rosa; Sowa, Mathew E.; Selfors, Laura M.; White, Anne; Zervantonakis, Ioannis K.; Singh, Pragya; Dhakal, Sabin; Harper, J. Wade; Brugge, Joan S.

    2016-01-01

    Cell-cell adhesion is central to morphogenesis and maintenance of epithelial cell state. We previously identified 27 candidate cell-cell adhesion regulatory proteins (CCARPs) whose down-regulation disrupts epithelial cell-cell adhesion during collective migration. Using a protein interaction mapping strategy, we found that 18 CCARPs link to core components of adherens junctions or desmosomes. We further mapped linkages between the CCARPs and other known cell-cell adhesion proteins, including hits from recent screens uncovering novel components of E-cadherin adhesions. Mechanistic studies of one novel CCARP which links to multiple cell-cell adhesion proteins, the phosphatase DUSP23, revealed that it promotes dephosphorylation of β-catenin at Tyr 142 and enhances the interaction between α- and β-catenin. DUSP23 knockdown specifically diminished adhesion to E-cadherin without altering adhesion to fibronectin matrix proteins. Furthermore, DUSP23 knockdown produced “zipper-like” cell-cell adhesions, caused defects in transmission of polarization cues, and reduced coordination during collective migration. Thus, this study identifies multiple novel connections between proteins that regulate cell-cell interactions and provides evidence for a previously unrecognized role for DUSP23 in regulating E-cadherin adherens junctions through promoting the dephosphorylation of β-catenin. PMID:27255161

  5. Characterization of toposomes from sea urchin blastula cells: a cell organelle mediating cell adhesion and expressing positional information.

    PubMed Central

    Noll, H; Matranga, V; Cervello, M; Humphreys, T; Kuwasaki, B; Adelson, D

    1985-01-01

    Cell adhesion in the sea urchin blastula is mediated by a 22S genus-specific glycoprotein complex consisting initially of six 160-kDa subunits that are processed proteolytically as development proceeds. Noncytolytic removal of the 22S particle from the surface with either 2.5% butanol or trypsin renders dissociated cells reaggregation incompetent, and addition restores reaggregation and development. Polyclonal antibodies against the 22S complex prevent reaggregation in a genus-specific manner while monoclonal antibodies stain cell surface structures in a pattern consistent with a code that specifies the position of a cell in the embryo by a unique combination of subunits in its cell adhesion particles. The existence of similar particles in Drosophila and amphibian embryos suggests that these glycoprotein complexes are a general class of organelles, the toposomes, that in the embryo mediate cell adhesion and express positional information. Images PMID:3865216

  6. Cytoplasmic Domain of Zebrafish Myelin Protein Zero: Adhesive Role Depends on β-Conformation

    PubMed Central

    Luo, XiaoYang; Inouye, Hideyo; Gross, Abby A. R.; Hidalgo, Marla M.; Sharma, Deepak; Lee, Daniel; Avila, Robin L.; Salmona, Mario; Kirschner, Daniel A.

    2007-01-01

    Solution spectroscopy studies on the cytoplasmic domain of human myelin protein zero (P0) (hP0-cyt) suggest that H-bonding between β-strands from apposed molecules is likely responsible for the tight cytoplasmic apposition in compact myelin. As a follow-up to these findings, in the current study we used circular dichroism and x-ray diffraction to analyze the same type of model membranes previously used for hP0-cyt to investigate the molecular mechanism underlying the zebrafish cytoplasmic apposition. This space is significantly narrower in teleosts compared with that in higher vertebrates, and can be accounted for in part by the much shorter cytoplasmic domain in the zebrafish protein (zP0-cyt). Circular dichroism measurements on zP0-cyt showed similar structural characteristics to those of hP0-cyt, i.e., the protein underwent a β→α structural transition at lipid/protein (L/P) molar ratios >50, and adopted a β-conformation at lower L/P molar ratios. X-ray diffraction was carried out on lipid vesicle solutions with zP0-cyt before and after dehydration to study the effect of protein on membrane lipid packing. Solution diffraction revealed the electron-density profile of a single membrane bilayer. Diffraction patterns of dried samples suggested a multilamellar structure with the β-folded P0-cyt located at the intermembrane space. Our findings support the idea that the adhesive role of P0 at the cytoplasmic apposition in compact myelin depends on the cytoplasmic domain of P0 being in the β-conformation. PMID:17693467

  7. Engineering Genes for Predictable Protein Expression

    PubMed Central

    Gustafsson, Claes; Minshull, Jeremy; Govindarajan, Sridhar; Ness, Jon; Villalobos, Alan; Welch, Mark

    2013-01-01

    The DNA sequence used to encode a polypeptide can have dramatic effects on its expression. Lack of readily available tools has until recently inhibited meaningful experimental investigation of this phenomenon. Advances in synthetic biology and the application of modern engineering approaches now provide the tools for systematic analysis of the sequence variables affecting heterologous expression of recombinant proteins. We here discuss how these new tools are being applied and how they circumvent the constraints of previous approaches, highlighting some of the surprising and promising results emerging from the developing field of gene engineering. PMID:22425659

  8. Engineering genes for predictable protein expression.

    PubMed

    Gustafsson, Claes; Minshull, Jeremy; Govindarajan, Sridhar; Ness, Jon; Villalobos, Alan; Welch, Mark

    2012-05-01

    The DNA sequence used to encode a polypeptide can have dramatic effects on its expression. Lack of readily available tools has until recently inhibited meaningful experimental investigation of this phenomenon. Advances in synthetic biology and the application of modern engineering approaches now provide the tools for systematic analysis of the sequence variables affecting heterologous expression of recombinant proteins. We here discuss how these new tools are being applied and how they circumvent the constraints of previous approaches, highlighting some of the surprising and promising results emerging from the developing field of gene engineering.

  9. Adsorption and adhesion of common serum proteins to nanotextured gallium nitride

    NASA Astrophysics Data System (ADS)

    Bain, Lauren E.; Hoffmann, Marc P.; Bryan, Isaac; Collazo, Ramón; Ivanisevic, Albena

    2015-01-01

    , particularly when considering biological systems. It is well known that thin films and nanostructures feature different optical, electrical, and mechanical properties from their bulk composites; however, interactions taking place at the interface between nanomaterials and their surroundings are less understood. Here, we explore interactions between common serum proteins - serum albumin, fibrinogen, and immunoglobulin G - and a nanotextured gallium nitride surface. Atomic force microscopy with a carboxyl-terminated colloid tip is used to probe the `activity' of proteins adsorbed onto the surface, including both the accessibility of the terminal amine to the tip as well as the potential for protein extension. By evaluating the frequency of tip-protein interactions, we can establish differences in protein behaviour on the basis of both the surface roughness as well as morphology, providing an assessment of the role of surface texture in dictating protein-surface interactions. Unidirectional surface features - either the half-unit cell steppes of as-grown GaN or those produced by mechanical polishing - appear to promote protein accessibility, with a higher frequency of protein extension events taking place on these surfaces when compared with less ordered surface features. Development of a full understanding of the factors influencing surface-biomolecule interactions can pave the way for specific surface modification to tailor the bio-material interface, offering a new path for device optimization. Electronic supplementary information (ESI) available: Additional figures demonstrating the adhesion force magnitude (Fig. S1) and lateral steppe surface topography (Fig. S2). See DOI: 10.1039/c4nr06353h

  10. Testosterone attenuates expression of vascular cell adhesion molecule-1 by conversion to estradiol by aromatase in endothelial cells: implications in atherosclerosis.

    PubMed

    Mukherjee, Tapan K; Dinh, Hillary; Chaudhuri, Gautam; Nathan, Lauren

    2002-03-19

    We previously reported that testosterone attenuated atherogenesis in LDLR(-/-) male mice, and that this effect of testosterone was most likely caused by its conversion to estradiol. Estradiol inhibits vascular cell adhesion molecule-1 (VCAM-1) expression, and expression of VCAM-1 is one of the early events in atherogenesis. We assessed the cellular mechanism(s) involved by which testosterone attenuates atherogenesis. We evaluated whether testosterone inhibited TNFalpha-induced VCAM-1 expression via its conversion to estradiol by the enzyme aromatase in human umbilical vein endothelial cells (HUVEC). Aromatase mRNA was dedected by reverse transcription-PCR in these cells. Testosterone (30 nM-1 microM) attenuated VCAM-1 mRNA expression in a concentration-dependent manner. The non aromatizable androgen, dihydrotestosterone, had no effect on VCAM-1 mRNA expression. Testosterone was less effective in attenuating VCAM-1 expression in the presence of anastrozole, an inhibitor of aromatase, indicating that testosterone inhibited VCAM-1 via conversion to estradiol. Estradiol also attenuated VCAM-1 mRNA expression, but this action was not abolished in the presence of anastrozole, indicating that anastrozole itself did not modulate VCAM-1 mRNA expression. The effect of testosterone on VCAM-1 mRNA expression was inhibited in the presence of the estrogen receptor antagonist, ICI-182780. Testosterone also attenuated TNFalpha-induced VCAM-1 protein expression, and this attenuation was abolished in the presence of anastrozole. In conclusion, testosterone inhibited VCAM-1 mRNA and protein expression in HUVEC by its conversion to estradiol via the enzyme aromatase present in the endothelial cells. Results from our study may help explain the mechanism by which testosterone may have beneficial effects on the cardiovascular system.

  11. Maprotiline inhibits LPS-induced expression of adhesion molecules (ICAM-1 and VCAM-1) in human endothelial cells

    PubMed Central

    Rafiee, Laleh; Hajhashemi, Valiollah; Javanmard, Shaghayegh Haghjooy

    2016-01-01

    Regardless of the known anti-inflammatory potential of heterocyclic antidepressants, the mechanisms concerning their modulating effects are not completely known. In our earlier work, maprotiline, a heterocyclic antidepressants, considerably inhibited infiltration of polymorphonuclear cell leucocytes into the inflamed paw. To understand the mechanism involved, we evaluated the effect of vascular cell adhesion molecule (VCAM-1), intracellular adhesion molecule (ICAM-1) expression in stimulated endothelial cells. Endothelial cells were stimulated with lipopolysaccharide (LPS) in the presence and absence of maprotiline (10-8 to 10-6 M) and ICAM-1 and VCAM-1 expression were measured using real-time quantitative reverse transcription polymerase chain reaction. Maprotiline significantly decreased the LPS-induced expression of VCAM-1 at all applied concentrations. The expression of ICAM-1 decreased in the presence of maprotiline at 10-6 M concentration (P<0.05). Since maprotiline inhibits the expression of adhesion molecules, ICAM-1 and VCAM-1 in LPS-stimulated human endothelial cells, it can be a possible way through which maprotiline exerts its anti-inflammatory properties. PMID:27168753

  12. The adaptor protein SAP directly associates with PECAM-1 and regulates PECAM-1-mediated-cell adhesion in T-like cell lines.

    PubMed

    Proust, Richard; Crouin, Catherine; Gandji, Leslie Yewakon; Bertoglio, Jacques; Gesbert, Franck

    2014-04-01

    SAP is a small cytosolic adaptor protein expressed in hematopoietic lineages whose main function is to regulate intracellular signaling pathways induced by the triggering of members of the SLAM receptor family. In this paper, we have identified the adhesion molecule PECAM-1 as a new partner for SAP in a conditional yeast two-hybrid screen. PECAM-1 is an immunoglobulin-like molecule expressed by endothelial cells and leukocytes, which possesses both pro- and anti-inflammatory properties. However, little is known about PECAM-1 functions in T cells. We show that SAP directly and specifically interacts with the cytosolic tyrosine 686 of PECAM-1. We generated different T-like cell lines in which SAP or PECAM-1 are expressed or down modulated and we demonstrate that a diminished SAP expression correlates with a diminished PECAM-1-mediated adhesion. Although SAP has mainly been shown to associate with SLAM receptors, we evidence here that SAP is a new actor downstream of PECAM-1.

  13. Expression Differentiation Is Constrained to Low-Expression Proteins over Ecological Timescales.

    PubMed

    Margres, Mark J; Wray, Kenneth P; Seavy, Margaret; McGivern, James J; Herrera, Nathanael D; Rokyta, Darin R

    2016-01-01

    Protein expression level is one of the strongest predictors of protein sequence evolutionary rate, with high-expression protein sequences evolving at slower rates than low-expression protein sequences largely because of constraints on protein folding and function. Expression evolutionary rates also have been shown to be negatively correlated with expression level across human and mouse orthologs over relatively long divergence times (i.e., ∼100 million years). Long-term evolutionary patterns, however, often cannot be extrapolated to microevolutionary processes (and vice versa), and whether this relationship holds for traits evolving under directional selection within a single species over ecological timescales (i.e., <5000 years) is unknown and not necessarily expected. Expression is a metabolically costly process, and the expression level of a particular protein is predicted to be a tradeoff between the benefit of its function and the costs of its expression. Selection should drive the expression level of all proteins close to values that maximize fitness, particularly for high-expression proteins because of the increased energetic cost of production. Therefore, stabilizing selection may reduce the amount of standing expression variation for high-expression proteins, and in combination with physiological constraints that may place an upper bound on the range of beneficial expression variation, these constraints could severely limit the availability of beneficial expression variants. To determine whether rapid-expression evolution was restricted to low-expression proteins owing to these constraints on highly expressed proteins over ecological timescales, we compared venom protein expression levels across mainland and island populations for three species of pit vipers. We detected significant differentiation in protein expression levels in two of the three species and found that rapid-expression differentiation was restricted to low-expression proteins. Our

  14. PARP-1 protein expression in glioblastoma multiforme

    PubMed Central

    Galia, A.; Calogero, A.E.; Condorelli, R.A.; Fraggetta, F.; La Corte, C.; Ridolfo, F.; Bosco, P.; Castiglione, R.; Salemi, M.

    2012-01-01

    One of the most common type of primary brain tumors in adults is the glioblastoma multiforme (GBM) (World Health Organization grade IV astrocytoma). It is the most common malignant and aggressive form of glioma and it is among the most lethal ones. Poly (ADP-ribose) polymerase 1 (PARP-1) gene, located to 1q42, plays an important role for the efficient maintenance of genome integrity. PARP-1 protein is required for the apoptosis-inducing factor (AIF) translocation from the mitochondria to the nucleus. PARP-1 is proteolytically cleaved at the onset of apoptosis by caspase-3. Microarray analysis of PARP-1 gene expression in more than 8000 samples revealed that PARP-1 is more highly expressed in several types of cancer compared with the equivalent normal tissues. Overall, the most differences in PARP-1 gene expression have been observed in breast, ovarian, endometrial, lung, and skin cancers, and non-Hodgkin's lymphoma. We evaluated the expression of PARP-1 protein in normal brain tissues and primary GBM by immunohistochemistry. Positive nuclear PARP-1 staining was found in all samples with GBM, but not in normal neurons from controls (n=4) and GBM patients (n=27). No cytoplasmic staining was observed in any sample. In conclusion, PARP-1 gene is expressed in GBM. This finding may be envisioned as an attempt to trigger apoptosis in this tumor, as well as in many other malignancies. The presence of the protein exclusively at the nucleus further support the function played by this gene in genome integrity maintenance and apoptosis. Finally, PARP-1 staining may be used as GBM cell marker. PMID:22472897

  15. Pathogenic Naegleria fowleri and non-pathogenic Naegleria lovaniensis exhibit differential adhesion to, and invasion of, extracellular matrix proteins.

    PubMed

    Jamerson, Melissa; da Rocha-Azevedo, Bruno; Cabral, Guy A; Marciano-Cabral, Francine

    2012-03-01

    Naegleria fowleri and Naegleria lovaniensis are closely related free-living amoebae found in the environment. N. fowleri causes primary amoebic meningoencephalitis (PAM), a rapidly fatal disease of the central nervous system, while N. lovaniensis is non-pathogenic. N. fowleri infection occurs when the amoebae access the nasal passages, attach to the nasal mucosa and its epithelial lining, and migrate to the brain. This process involves interaction with components of the host extracellular matrix (ECM). Since the ability to invade tissues can be a characteristic that distinguishes pathogenic from non-pathogenic amoebae, the objective of this study was to assess adhesion to, and invasion of, the ECM by these two related but distinct Naegleria species. N. fowleri exhibited a higher level of adhesion to the ECM components laminin-1, fibronectin and collagen I. Scanning electron microscopy revealed that N. fowleri attached on ECM substrata exhibited a spread-out appearance that included the presence of focal adhesion-like structures. Western immunoblotting revealed two integrin-like proteins for both species, but one of these, with a molecular mass of approximately 70 kDa, was detected at a higher level in N. fowleri. Confocal microscopy indicated that the integrin-like proteins co-localized to the focal adhesion-like structures. Furthermore, anti-integrin antibody decreased adhesion of N. fowleri to ECM components. Finally, N. fowleri disrupted 3D ECM scaffolds, while N. lovaniensis had a minimal effect. Collectively, these results indicate a distinction in adhesion to, and invasion of, ECM proteins between N. fowleri and N. lovaniensis.

  16. Pathogenic Naegleria fowleri and non-pathogenic Naegleria lovaniensis exhibit differential adhesion to, and invasion of, extracellular matrix proteins

    PubMed Central

    Jamerson, Melissa; da Rocha-Azevedo, Bruno; Cabral, Guy A.

    2012-01-01

    Naegleria fowleri and Naegleria lovaniensis are closely related free-living amoebae found in the environment. N. fowleri causes primary amoebic meningoencephalitis (PAM), a rapidly fatal disease of the central nervous system, while N. lovaniensis is non-pathogenic. N. fowleri infection occurs when the amoebae access the nasal passages, attach to the nasal mucosa and its epithelial lining, and migrate to the brain. This process involves interaction with components of the host extracellular matrix (ECM). Since the ability to invade tissues can be a characteristic that distinguishes pathogenic from non-pathogenic amoebae, the objective of this study was to assess adhesion to, and invasion of, the ECM by these two related but distinct Naegleria species. N. fowleri exhibited a higher level of adhesion to the ECM components laminin-1, fibronectin and collagen I. Scanning electron microscopy revealed that N. fowleri attached on ECM substrata exhibited a spread-out appearance that included the presence of focal adhesion-like structures. Western immunoblotting revealed two integrin-like proteins for both species, but one of these, with a molecular mass of approximately 70 kDa, was detected at a higher level in N. fowleri. Confocal microscopy indicated that the integrin-like proteins co-localized to the focal adhesion-like structures. Furthermore, anti-integrin antibody decreased adhesion of N. fowleri to ECM components. Finally, N. fowleri disrupted 3D ECM scaffolds, while N. lovaniensis had a minimal effect. Collectively, these results indicate a distinction in adhesion to, and invasion of, ECM proteins between N. fowleri and N. lovaniensis. PMID:22222499

  17. Multifunctional and Redundant Roles of Borrelia burgdorferi Outer Surface Proteins in Tissue Adhesion, Colonization, and Complement Evasion

    PubMed Central

    Caine, Jennifer A.; Coburn, Jenifer

    2016-01-01

    Borrelia burgdorferi is the causative agent of Lyme disease in the U.S., with at least 25,000 cases reported to the CDC each year. B. burgdorferi is thought to enter and exit the bloodstream to achieve rapid dissemination to distal tissue sites during infection. Travel through the bloodstream requires evasion of immune surveillance and pathogen clearance in the host, a process at which B. burgdorferi is adept. B. burgdorferi encodes greater than 19 adhesive outer surface proteins many of which have been found to bind to host cells or components of the extracellular matrix. Several others bind to host complement regulatory factors, in vitro. Production of many of these adhesive proteins is tightly regulated by environmental cues, and some have been shown to aid in vascular interactions and tissue colonization, as well as survival in the blood, in vivo. Recent work has described multifaceted and redundant roles of B. burgdorferi outer surface proteins in complement component interactions and tissue targeted adhesion and colonization, distinct from their previously identified in vitro binding capabilities. Recent insights into the multifunctional roles of previously well-characterized outer surface proteins such as BBK32, DbpA, CspA, and OspC have changed the way we think about the surface proteome of these organisms during the tick–mammal life cycle. With the combination of new and old in vivo models and in vitro techniques, the field has identified distinct ligand binding domains on BBK32 and DbpA that afford tissue colonization or blood survival to B. burgdorferi. In this review, we describe the multifunctional and redundant roles of many adhesive outer surface proteins of B. burgdorferi in tissue adhesion, colonization, and bloodstream survival that, together, promote the survival of Borrelia spp. throughout maintenance in their multi-host lifestyle. PMID:27818662

  18. The Src homology 2 protein Shb promotes cell cycle progression in murine hematopoietic stem cells by regulation of focal adhesion kinase activity

    SciTech Connect

    Gustafsson, Karin; Heffner, Garrett; Wenzel, Pamela L.; Curran, Matthew; Grawé, Jan; McKinney-Freeman, Shannon L.; Daley, George Q.; Welsh, Michael

    2013-07-15

    The widely expressed adaptor protein Shb has previously been reported to contribute to T cell function due to its association with the T cell receptor and furthermore, several of Shb's known interaction partners are established regulators of blood cell development and function. In addition, Shb deficient embryonic stem cells displayed reduced blood cell colony formation upon differentiation in vitro. The aim of the current study was therefore to explore hematopoietic stem and progenitor cell function in the Shb knockout mouse. Shb deficient bone marrow contained reduced relative numbers of long-term hematopoietic stem cells (LT-HSCs) that exhibited lower proliferation rates. Despite this, Shb knockout LT-HSCs responded promptly by entering the cell cycle in response to genotoxic stress by 5-fluorouracil treatment. In competitive LT-HSC transplantations, Shb null cells initially engrafted as well as the wild-type cells but provided less myeloid expansion over time. Moreover, Shb knockout bone marrow cells exhibited elevated basal activities of focal adhesion kinase/Rac1/p21-activated kinase signaling and reduced responsiveness to Stem Cell Factor stimulation. Consequently, treatment with a focal adhesion kinase inhibitor increased Shb knockout LT-HSC proliferation. The altered signaling characteristics thus provide a plausible mechanistic explanation for the changes in LT-HSC proliferation since these signaling intermediates have all been shown to participate in LT-HSC cell cycle control. In summary, the loss of Shb dependent signaling in bone marrow cells, resulting in elevated focal adhesion kinase activity and reduced proliferative responses in LT-HSCs under steady state hematopoiesis, confers a disadvantage to the maintenance of LT-HSCs over time. -- Highlights: • Shb is an adaptor protein operating downstream of tyrosine kinase receptors. • Shb deficiency reduces hematopoietic stem cell proliferation. • The proliferative effect of Shb occurs via increased

  19. Detection of Staphylococcus aureus adhesion and biofilm-producing genes and their expression during internalization in bovine mammary epithelial cells.

    PubMed

    Pereyra, Elizabet A L; Picech, Florencia; Renna, María S; Baravalle, Celina; Andreotti, Carolina S; Russi, Romina; Calvinho, Luis F; Diez, Cristina; Dallard, Bibiana E

    2016-02-01

    Staphylococcus aureus is one of the most prevalent pathogens isolated from bovine mastitis, causing chronic intramammary infections (IMI) that limit profitable dairying. The course of infection is often associated with factors both related to the host and the bacterium. Aims of this study were to select S. aureus isolates from bovine IMI with different genotypic profiles harboring genes involved in adherence and biofilm production, to determine the behavior of these strains in contact with bovine mammary epithelial cells (MAC-T) and the expression of those genes during bacterial-cell early interactions. The genetic diversity of 20 S. aureus strains that were isolated from milk samples taken from cows with persistent-P and non-persistent-NP IMI was high, discriminated into 13 fingerprint groups. The occurrence of genes coding for S. aureus surface proteins (clfA, clfB, fnbA, fnbB, fib, cna) and biofilm formation (icaA, icaD, icaC, bap) and in vitro biofilm-forming ability was not related to strain clinical origin (NP or P). Internalization of S. aureus into MAC-T cells was strain-dependent and internalized bacteria overexpressed adherence and biofilm-forming genes compared with those that remained in the supernatant of co-cultures; particularly those genes encoding FnBPs and IcaD. Strains yielding highest invasion percentages were those able to overexpress fnBP, irrespectively of the presence of other evaluated genes. Strains from NP IMI showed a greater multiplication capacity in vitro compared with strains from P IMI. These results provide new insights about S. aureus differential gene expression of adhesion-internalization factors during early interaction with mammary epithelial cells.

  20. Myelin Basic Protein Cleaves Cell Adhesion Molecule L1 and Promotes Neuritogenesis and Cell Survival*

    PubMed Central

    Lutz, David; Loers, Gabriele; Kleene, Ralf; Oezen, Iris; Kataria, Hardeep; Katagihallimath, Nainesh; Braren, Ingke; Harauz, George; Schachner, Melitta

    2014-01-01

    The cell adhesion molecule L1 is a Lewisx-carrying glycoprotein that plays important roles in the developing and adult nervous system. Here we show that myelin basic protein (MBP) binds to L1 in a Lewisx-dependent manner. Furthermore, we demonstrate that MBP is released by murine cerebellar neurons as a sumoylated dynamin-containing protein upon L1 stimulation and that this MBP cleaves L1 as a serine protease in the L1 extracellular domain at Arg687 yielding a transmembrane fragment that promotes neurite outgrowth and neuronal survival in cell culture. L1-induced neurite outgrowth and neuronal survival are reduced in MBP-deficient cerebellar neurons and in wild-type cerebellar neurons in the presence of an MBP antibody or L1 peptide containing the MBP cleavage site. Genetic ablation of MBP in shiverer mice and mutagenesis of the proteolytically active site in MBP or of the MBP cleavage site within L1 as well as serine protease inhibitors and an L1 peptide containing the MBP cleavage site abolish generation of the L1 fragment. Our findings provide evidence for novel functions of MBP in the nervous system. PMID:24671420

  1. Universal method for protein bioconjugation with nanocellulose scaffolds for increased cell adhesion.

    PubMed

    Kuzmenko, Volodymyr; Sämfors, Sanna; Hägg, Daniel; Gatenholm, Paul

    2013-12-01

    Bacterial nanocellulose (BNC) is an emerging biomaterial since it is biocompatible, integrates well with host tissue and can be biosynthesized in desired architecture. However, being a hydrogel, it exhibits low affinity for cell attachment, which is crucial for the cellular fate process. To increase cell attachment, the surface of BNC scaffolds was modified with two proteins, fibronectin and collagen type I, using an effective bioconjugation method applying 1-cyano-4-dimethylaminopyridinium (CDAP) tetrafluoroborate as the intermediate catalytic agent. The effect of CDAP treatment on cell adhesion to the BNC surface is shown for human umbilical vein endothelial cells and the mouse mesenchymal stem cell line C3H10T1/2. In both cases, the surface modification increased the number of cells attached to the surfaces. In addition, the morphology of the cells indicated more healthy and viable cells. CDAP activation of bacterial nanocellulose is shown to be a convenient method to conjugate extracellular proteins to the scaffold surfaces. CDAP treatment can be performed in a short period of time in an aqueous environment under heterogeneous and mild conditions preserving the nanofibrillar network of cellulose.

  2. New functions and signaling mechanisms for the class of adhesion G protein-coupled receptors.

    PubMed

    Liebscher, Ines; Ackley, Brian; Araç, Demet; Ariestanti, Donna M; Aust, Gabriela; Bae, Byoung-il; Bista, Bigyan R; Bridges, James P; Duman, Joseph G; Engel, Felix B; Giera, Stefanie; Goffinet, André M; Hall, Randy A; Hamann, Jörg; Hartmann, Nicole; Lin, Hsi-Hsien; Liu, Mingyao; Luo, Rong; Mogha, Amit; Monk, Kelly R; Peeters, Miriam C; Prömel, Simone; Ressl, Susanne; Schiöth, Helgi B; Sigoillot, Séverine M; Song, Helen; Talbot, William S; Tall, Gregory G; White, James P; Wolfrum, Uwe; Xu, Lei; Piao, Xianhua

    2014-12-01

    The class of adhesion G protein-coupled receptors (aGPCRs), with 33 human homologs, is the second largest family of GPCRs. In addition to a seven-transmembrane α-helix-a structural feature of all GPCRs-the class of aGPCRs is characterized by the presence of a large N-terminal extracellular region. In addition, all aGPCRs but one (GPR123) contain a GPCR autoproteolysis-inducing (GAIN) domain that mediates autoproteolytic cleavage at the GPCR autoproteolysis site motif to generate N- and a C-terminal fragments (NTF and CTF, respectively) during protein maturation. Subsequently, the NTF and CTF are associated noncovalently as a heterodimer at the plasma membrane. While the biological function of the GAIN domain-mediated autocleavage is not fully understood, mounting evidence suggests that the NTF and CTF possess distinct biological activities in addition to their function as a receptor unit. We discuss recent advances in understanding the biological functions, signaling mechanisms, and disease associations of the aGPCRs.

  3. Expression of the melanoma cell adhesion molecule in human mesenchymal stromal cells regulates proliferation, differentiation, and maintenance of hematopoietic stem and progenitor cells.

    PubMed

    Stopp, Sabine; Bornhäuser, Martin; Ugarte, Fernando; Wobus, Manja; Kuhn, Matthias; Brenner, Sebastian; Thieme, Sebastian

    2013-04-01

    The melanoma cell adhesion molecule defines mesenchymal stromal cells in the human bone marrow that regenerate bone and establish a hematopoietic microenvironment in vivo. The role of the melanoma cell adhesion molecule in primary human mesenchymal stromal cells and the maintenance of hematopoietic stem and progenitor cells during ex vivo culture has not yet been demonstrated. We applied RNA interference or ectopic overexpression of the melanoma cell adhesion molecule in human mesenchymal stromal cells to evaluate the effect of the melanoma cell adhesion molecule on their proliferation and differentiation as well as its influence on co-cultivated hematopoietic stem and progenitor cells. Knockdown and overexpression of the melanoma cell adhesion molecule affected several characteristics of human mesenchymal stromal cells related to osteogenic differentiation, proliferation, and migration. Furthermore, knockdown of the melanoma cell adhesion molecule in human mesenchymal stromal cells stimulated the proliferation of hematopoietic stem and progenitor cells, and strongly reduced the formation of long-term culture-initiating cells. In contrast, melanoma cell adhesion molecule-overexpressing human mesenchymal stromal cells provided a supportive microenvironment for hematopoietic stem and progenitor cells. Expression of the melanoma cell adhesion molecule increased the adhesion of hematopoietic stem and progenitor cells to human mesenchymal stromal cells and their migration beneath the monolayer of human mesenchymal stromal cells. Our results demonstrate that the expression of the melanoma cell adhesion molecule in human mesenchymal stromal cells determines their fate and regulates the maintenance of hematopoietic stem and progenitor cells through direct cell-cell contact.

  4. Heat shock protein 90β stabilizes focal adhesion kinase and enhances cell migration and invasion in breast cancer cells

    SciTech Connect

    Xiong, Xiangyang; Wang, Yao; Liu, Chengmei; Lu, Quqin; Liu, Tao; Chen, Guoan; Rao, Hai; Luo, Shiwen

    2014-08-01

    Focal adhesion kinase (FAK) acts as a regulator of cellular signaling and may promote cell spreading, motility, invasion and survival in malignancy. Elevated expression and activity of FAK frequently correlate with tumor cell metastasis and poor prognosis in breast cancer. However, the mechanisms by which the turnover of FAK is regulated remain elusive. Here we report that heat shock protein 90β (HSP90β) interacts with FAK and the middle domain (amino acids 233–620) of HSP90β is mainly responsible for this interaction. Furthermore, we found that HSP90β regulates FAK stability since HSP90β inhibitor 17-AAG triggers FAK ubiquitylation and subsequent proteasome-dependent degradation. Moreover, disrupted FAK-HSP90β interaction induced by 17-AAG contributes to attenuation of tumor cell growth, migration, and invasion. Together, our results reveal how HSP90β regulates FAK stability and identifies a potential therapeutic strategy to breast cancer. - Highlights: • HSP90β protects FAK from degradation by the ubiquitin-proteasome pathway. • Inhibition of HSP90β or FAK attenuates tumorigenesis of breast cancer cells. • Genetic repression of HSP90β or FAK inhibits tumor cell migration and proliferation. • Inhibition of HSP90β or FAK interferes cell invasion and cytoskeleton.

  5. Adhesion Protein ApfA of Actinobacillus pleuropneumoniae Is Required for Pathogenesis and Is a Potential Target for Vaccine Development

    PubMed Central

    Zhou, Yang; Li, Lu; Chen, Zhaohui; Yuan, Hong; Chen, Huanchun

    2013-01-01

    Actinobacillus pleuropneumoniae is the etiologic agent of porcine pleuropneumonia, which causes serious economic losses in the pig farming industry worldwide. Due to a lack of knowledge of its virulence factors and a lack of effective vaccines able to confer cross-serotype protection, it is difficult to place this disease under control. By analyzing its genome sequences, we found that type IV fimbrial subunit protein ApfA is highly conserved among different serotypes of A. pleuropneumoniae. Our study shows that ApfA is an adhesin since its expression was greatly upregulated (135-fold) upon contact with host cells, while its deletion mutant attenuated its capability of adhesion. The inactivation of apfA dramatically reduced the ability of A. pleuropneumoniae to colonize mouse lung, suggesting that apfA is a virulence factor. Purified recombinant ApfA elicited an elevated humoral immune response and conferred robust protection against challenges with A. pleuropneumoniae serovar 1 strain 4074 and serovar 7 strain WF83 in mice. Importantly, the anti-ApfA serum conferred significant protection against both serovar 1 and serovar 7 in mice. These studies indicate that ApfA promotes virulence through attachment to host cells, and its immunogenicity renders it a promising novel subunit vaccine candidate against infection with A. pleuropneumoniae. PMID:23269417

  6. A family of ROP proteins that suppresses actin dynamics, and is essential for polarized growth and cell adhesion.

    PubMed

    Burkart, Graham M; Baskin, Tobias I; Bezanilla, Magdalena

    2015-07-15

    In plants, the ROP family of small GTPases has been implicated in the polarized growth of tip-growing cells, such as root hairs and pollen tubes; however, most of the data derive from overexpressing ROP genes or constitutively active and dominant-negative isoforms, whereas confirmation by using loss-of-function studies has generally been lacking. Here, in the model moss Physcomitrella patens, we study ROP signaling during tip growth by using a loss-of-function approach based on RNA interference (RNAi) to silence the entire moss ROP family. We find that plants with reduced expression of ROP genes, in addition to failing to initiate tip growth, have perturbed cell wall staining, reduced cell adhesion and have increased actin-filament dynamics. Although plants subjected to RNAi against the ROP family also have reduced microtubule dynamics, this reduction is not specific to loss of ROP genes, as it occurs when actin function is compromised chemically or genetically. Our data suggest that ROP proteins polarize the actin cytoskeleton by suppressing actin-filament dynamics, leading to an increase in actin filaments at the site of polarized secretion.

  7. RhoGAP68F controls transport of adhesion proteins in Rab4 endosomes to modulate epithelial morphogenesis of Drosophila leg discs

    PubMed Central

    de Madrid, Beatriz Hernandez; Greenberg, Lina; Hatini, Victor

    2015-01-01

    SUMMARY Elongation and invagination of epithelial tissues are fundamental developmental processes that contribute to the morphogenesis of embryonic and adult structures and are dependent on coordinated remodeling of cell-cell contacts. The morphogenesis of Drosophila leg imaginal discs depends on extensive remodeling of cell contacts and thus provides a useful system with which to investigate the underlying mechanisms. The small Rho GTPase regulator RhoGAP68F has been previously implicated in leg morphogenesis. It consists of an N-terminal Sec14 domain and a C-terminal GAP domain. Here we examined the molecular function and role of RhoGAP68F in epithelial remodeling. We find that depletion of RhoGAP68F impairs epithelial remodeling from a pseudostratified to simple, while overexpression of RhoGAP68F causes tears of lateral cell-cell contacts and thus impairs epithelial integrity. We show that the RhoGAP68F protein localizes to Rab4 recycling endosomes and forms a complex with the Rab4 protein. The Sec14 domain is sufficient for localizing to Rab4 endosomes, while the activity of the GAP domain is dispensable. RhoGAP68F, in turn, inhibits the scission and movement of Rab4 endosomes involved in transport the adhesion proteins Fasciclin3 and E-cadherin back to cell-cell contacts. Expression of RhoGAP68F is upregulated during prepupal development suggesting that RhoGAP68F decreases the transport of key adhesion proteins to the cell surface during this developmental stage to decrease the strength of adhesive cell-cell contacts and thereby facilitate epithelial remodeling and leg morphogenesis. PMID:25617722

  8. Multiscale approaches to protein-mediated interactions between membranes—relating microscopic and macroscopic dynamics in radially growing adhesions

    NASA Astrophysics Data System (ADS)

    Bihr, Timo; Seifert, Udo; Smith, Ana-Sunčana

    2015-08-01

    Macromolecular complexation leading to coupling of two or more cellular membranes is a crucial step in a number of biological functions of the cell. While other mechanisms may also play a role, adhesion always involves the fluctuations of deformable membranes, the diffusion of proteins and the molecular binding and unbinding. Because these stochastic processes couple over a multitude of time and length scales, theoretical modeling of membrane adhesion has been a major challenge. Here we present an effective Monte Carlo scheme within which the effects of the membrane are integrated into local rates for molecular recognition. The latter step in the Monte Carlo approach enables us to simulate the nucleation and growth of adhesion domains within a system of the size of a cell for tens of seconds without loss of accuracy, as shown by comparison to 106 times more expensive Langevin simulations. To perform this validation, the Langevin approach was augmented to simulate diffusion of proteins explicitly, together with reaction kinetics and membrane dynamics. We use the Monte Carlo scheme to gain deeper insight to the experimentally observed radial growth of micron sized adhesion domains, and connect the effective rate with which the domain is growing to the underlying microscopic events. We thus demonstrate that our technique yields detailed information about protein transport and complexation in membranes, which is a fundamental step toward understanding even more complex membrane interactions in the cellular context.

  9. Regulation of the L-type calcium channel by alpha 5beta 1 integrin requires signaling between focal adhesion proteins.

    PubMed

    Wu, X; Davis, G E; Meininger, G A; Wilson, E; Davis, M J

    2001-08-10

    The L-type calcium channel is the major calcium influx pathway in vascular smooth muscle and is regulated by integrin ligands, suggesting an important link between extracellular matrix and vascular tone regulation in tissue injury and remodeling. We examined the role of integrin-linked tyrosine kinases and focal adhesion proteins in regulation of L-type calcium current in single vascular myocytes. Soluble tyrosine kinase inhibitors blocked the increase in current produced by alpha(5) integrin antibody or fibronectin, whereas tyrosine phosphatase inhibition enhanced the effect. Cell dialysis with an antibody to focal adhesion kinase or with FRNK, the C-terminal noncatalytic domain of focal adhesion kinase, produced moderate (24 or 18%, respectively) inhibition of basal current but much greater inhibition (63 or 68%, respectively) of integrin-enhanced current. A c-Src antibody and peptide inhibitors of the Src homology-2 domain or a putative Src tyrosine phosphorylation site on the channel produced similar inhibition. Antibodies to the cytoskeletal proteins paxillin and vinculin, but not alpha-actinin, inhibited integrin-dependent current by 65-80%. Therefore, alpha(5)beta(1) integrin appears to regulate a tyrosine phosphorylation cascade involving Src and various focal adhesion proteins that control the function of the L-type calcium channel. This interaction may represent a novel mechanism for control of calcium influx in vascular smooth muscle and other cell types.

  10. Cell adhesion to proteins separated by lithium dodecyl sulfate-polyacrylamide gel electrophoresis and blotted onto a polyvinylidene difluoride membrane: a new cell-blotting technique.

    PubMed

    Seshi, B

    1994-12-02

    Cell blotting, although conceptually simple, has failed to achieve wide practical application. Described here is a new cell-blotting technique which involves cell adhesion to protein bands after separation by lithium dodecyl sulfate-polyacrylamide gel electrophoresis (LDS-PAGE) and blotting onto polyvinylidene difluoride (PVDF) membrane at 4 degrees C. Cell bands adherent on PVDF are detected using hematoxylin, or propidium iodide (PI) staining followed by viewing under ultraviolet (UV) light. The technique allows quick microscopic visualization of adherent cells composing the bands, without requiring clearing of the membrane. Representative cell adhesion proteins from different sources, i.e., plant lectins (e.g., phytohemagglutinin, PHA; concanavalin A, ConA; and wheat germ agglutinin, WGA); extracellular matrix (ECM) proteins; and integral membrane proteins (e.g., recombinant soluble vascular cell adhesion molecule-1, rs VCAM-1) were tested for cell binding by the new cell-blotting technique using human lymphoid progenitor (NALM-6) and myeloid progenitor (KG1a) cell lines. Cell adhesion proteins retained their adhesion function in all cases tested. Specificity of cell binding on PVDF blot was demonstrated by inhibition of cell adhesion to WGA protein bands using an appropriate sugar, i.e., N-acetyl D-glucosamine. The cell blotting assay was comparable in sensitivity to Coomassie blue staining of protein bands. The ability to conduct protein extraction, separation and blotting at low temperature avoids thermal denaturation, thereby preserving the adhesion properties of the proteins. The electrophoretic/blotting system has unique detergent removal/protein renaturation properties and the ability to preserve functionally active adhesion protein complexes. The cell-blotting technique described is sufficiently robust for routine application in the investigation of novel cell adhesion proteins.

  11. Proteinaceous determinants of surface colonization in bacteria: bacterial adhesion and biofilm formation from a protein secretion perspective

    PubMed Central

    Chagnot, Caroline; Zorgani, Mohamed A.; Astruc, Thierry; Desvaux, Mickaël

    2013-01-01

    Bacterial colonization of biotic or abiotic surfaces results from two quite distinct physiological processes, namely bacterial adhesion and biofilm formation. Broadly speaking, a biofilm is defined as the sessile development of microbial cells. Biofilm formation arises following bacterial adhesion but not all single bacterial cells adhering reversibly or irreversibly engage inexorably into a sessile mode of growth. Among molecular determinants promoting bacterial colonization, surface proteins are the most functionally diverse active components. To be present on the bacterial cell surface, though, a protein must be secreted in the first place. Considering the close association of secreted proteins with their cognate secretion systems, the secretome (which refers both to the secretion systems and their protein substrates) is a key concept to apprehend the protein secretion and related physiological functions. The protein secretion systems are here considered in light of the differences in the cell-envelope architecture between diderm-LPS (archetypal Gram-negative), monoderm (archetypal Gram-positive) and diderm-mycolate (archetypal acid-fast) bacteria. Besides, their cognate secreted proteins engaged in the bacterial colonization process are regarded from single protein to supramolecular protein structure as well as the non-classical protein secretion. This state-of-the-art on the complement of the secretome (the secretion systems and their cognate effectors) involved in the surface colonization process in diderm-LPS and monoderm bacteria paves the way for future research directions in the field. PMID:24133488

  12. Paeonia lactiflora Enhances the Adhesion of Trophoblast to the Endometrium via Induction of Leukemia Inhibitory Factor Expression

    PubMed Central

    Park, Mi-Ju; Lee, Kyu Sup; Yoon, Youngjin; Kim, Hyung Sik; Lee, Jun Hee; Kwon, Sang-Mo; Lee, Syng-Ook; Kim, Keuk-Jun; Baek, Jin-Ho; Ha, Ki-Tae

    2016-01-01

    In the present study, we investigated the role of Paeonia lactiflora Pall. extract on embryo implantation in vitro and in vivo. A polysaccharides depleted-water extract of P. lactiflora (PL-PP) increased LIF expression in human endometrial Ishikawa cells at non-cytotoxic doses. PL-PP significantly increased the adhesion of the human trophectoderm-derived JAr spheroids to endometrial Ishikawa cells. PL-PP-induced LIF expression was decreased in the presence of a p38 kinase inhibitor SB203580 and an MEK/ERK inhibitor U0126. Furthermore, endometrial LIF knockdown by shRNA reduced the expression of integrins β3 and β5 and adhesion of JAr spheroids to Ishikawa cells. In vivo administration of PL-PP restored the implantation of mouse blastocysts in a mifepristone-induced implantation failure mice model. Our results demonstrate that PL-PP increases LIF expression via the p38 and MEK/ERK pathways and favors trophoblast adhesion to endometrial cells. PMID:26839969

  13. Estrogen and pure antiestrogen fulvestrant (ICI 182 780) augment cell–matrigel adhesion of MCF-7 breast cancer cells through a novel G protein coupled estrogen receptor (GPR30)-to-calpain signaling axis

    SciTech Connect

    Chen, Yan; Li, Zheng; He, Yan; Shang, Dandan; Pan, Jigang; Wang, Hongmei; Chen, Huamei; Zhu, Zhuxia; Wang, Xudong

    2014-03-01

    Fulvestrant (ICI 182 780, ICI) has been used in treating patients with hormone-sensitive breast cancer, yet initial or acquired resistance to endocrine therapies frequently arises and, in particular, cancer recurs as metastasis. We demonstrate here that both 17-beta-estradiol (E2) and ICI enhance cell adhesion to matrigel in MCF-7 breast cancer cells, with increased autolysis of calpain 1 (large subunit) and proteolysis of focal adhesion kinase (FAK), indicating calpain activation. Additionally, either E2 or ICI induced down-regulation of estrogen receptor α without affecting G protein coupled estrogen receptor 30 (GPR30) expression. Interestingly, GPR30 agonist G1 triggered calpain 1 autolysis but not calpain 2, whereas ER agonist diethylstilbestrol caused no apparent calpain autolysis. Furthermore, the actions of E2 and ICI on calpain and cell adhesion were tremendously suppressed by G15, or knockdown of GPR30. E2 and ICI also induced phosphorylation of extracellular regulated protein kinases 1 and 2 (ERK1/2), and suppression of ERK1/2 phosphorylation by U0126 profoundly impeded calpain activation triggered by estrogenic and antiestrogenic stimulations indicating implication of ERK1/2 in the GPR30-mediated action. Lastly, the E2- or ICI-induced cell adhesion was dramatically impaired by calpain-specific inhibitors, ALLN or calpeptin, suggesting requirement of calpain in the GPR30-associated action. These data show that enhanced cell adhesion by E2 and ICI occurs via a novel GPR30-ERK1/2-calpain pathway. Our results indicate that targeting the GPR30 signaling may be a potential strategy to reduce metastasis and improve the efficacy of antiestrogens in treatment of advanced breast cancer. - Highlights: • Estrogen and ICI augment adhesion to matrigel with calpain activation in MCF-7 cells. • GPR30 mediates cell–matrigel adhesion and calpain activation via ERK1/2. • Calpain is required in the cell–matrigel adhesion induced by E2 and ICI.

  14. Composites containing albumin protein or cyanoacrylate adhesives and biodegradable scaffolds: II. In vivo wound closure study in a rat model

    NASA Astrophysics Data System (ADS)

    McNally-Heintzelman, Karen M.; Heintzelman, Douglas L.; Duffy, Mark T.; Bloom, Jeffrey N.; Soller, Eric C.; Gilmour, Travis M.; Hoffman, Grant T.; Edward, Deepak

    2004-07-01

    Our Scaffold-Enhanced Biological Adhesive (SEBA) system was investigated as an alternative to sutures or adhesives alone for repair of wounds. Two scaffold materials were investigated: (i) a synthetic biodegradable material fabricated from poly(L-lactic-co-glycolic acid); and (ii) a biologic material, small intestinal submucosa, manufactured by Cook BioTech. Two adhesive materials were also investigated: (i) a biologic adhesive composed of 50%(w/v) bovine serum albumin solder and 0.5mg/ml indocyanine green dye mixed in deionized water, and activated with an 808-nm diode laser; and (ii) Ethicon"s Dermabond, a 2-octyl-cyanoacrylate. The tensile strength and time-to-failure of skin incisions repaired in vivo in a rat model were measured at seven days postoperative. Incisions closed by protein solder alone, by Dermabond alone, or by suture, were also tested for comparison. The tensile strength of repairs formed using the SEBA system were 50% to 65% stronger than repairs formed by suture or either adhesive alone, with significantly less variations within each experimental group (average standard deviations of 15% for SEBA versus 38% for suture and 28% for adhesive alone). In addition, the time-to-failure curves showed a longevity not previously seen with the suture or adhesive alone techniques. The SEBA system acts to keep the dermis in tight apposition during the critical early phase of wound healing when tissue gaps are bridged by scar and granulation tissue. It has the property of being more flexible than either of the adhesives alone and may allow the apposed edges to move in conjunction with each other as a unit for a longer period of time and over a greater range of stresses than adhesives alone. This permits more rapid healing and establishment of integrity since the microgaps between the dermis edges are significantly reduced. By the time the scaffolds are sloughed from the wound site, there is greater strength and healing than that produced by adhesive alone or

  15. Redox control of surface protein sulphhydryls in bovine spermatozoa reversibly modulates sperm adhesion to the oviductal epithelium and capacitation.

    PubMed

    Gualtieri, Roberto; Mollo, Valentina; Duma, Gennaro; Talevi, Riccardo

    2009-07-01

    Oviductal fluid molecules, such as sulphated glycosaminoglycans and disulphide-reductants, may represent periovulatory signals for the release of spermatozoa from the oviductal reservoir in the bovine species. Disulphide-reductants release spermatozoa through the reduction of sperm-surface disulphides to sulphhydryls (SH). Herein, we studied sperm-surface protein SH through labelling with maleimidylpropionyl biocytin in the initial sperm suspension, in the subpopulations able and unable to adhere to the in vitro cultured oviductal epithelium, and in spermatozoa released either through the disulphide-reductant penicillamine (PEN) or the sulphated glycosaminoglycan heparin (HEP). Adhesion assays were performed to study the ability of released spermatozoa to readhere to the oviductal epithelium. Results showed that the level of SH in sperm-surface proteins was: 1) low in adhering spermatozoa; 2) high in spermatozoa unable to adhere; and 3) markedly increased in released spermatozoa. Adhesion assays showed that: 1) PEN-released spermatozoa promptly recovered adhesion after removal of the disulphide-reductant and could be released again in response to PEN; 2) conversely, a limited number of HEP-released spermatozoa was able to readhere to the oviductal epithelium and this ability was not affected by HEP removal. Recovery of adhesion was associated to reoxidation of sperm-surface protein SH and to the reversal of capacitation. In conclusion, redox modulation of sperm-surface protein SH is involved in the release of spermatozoa adhering to the oviduct in vitro; the reversible action of disulphide-reductants might be responsible for intermittent phases of adhesions and releases; and the irreversible action of HEP indicates that it may represent a terminal releasing signal.

  16. Hydrogen sulfide augments neutrophil migration through enhancement of adhesion molecule expression and prevention of CXCR2 internalization: role of ATP-sensitive potassium channels.

    PubMed

    Dal-Secco, Daniela; Cunha, Thiago M; Freitas, Andressa; Alves-Filho, José Carlos; Souto, Fabrício O; Fukada, Sandra Y; Grespan, Renata; Alencar, Nylane M N; Neto, Alberto F; Rossi, Marcos A; Ferreira, Sérgio H; Hothersall, John S; Cunha, Fernando Q

    2008-09-15

    In this study, we have addressed the role of H(2)S in modulating neutrophil migration in either innate (LPS-challenged naive mice) or adaptive (methylated BSA (mBSA)-challenged immunized mice) immune responses. Treatment of mice with H(2)S synthesis inhibitors, dl-propargylglycine (PAG) or beta-cyanoalanine, reduced neutrophil migration induced by LPS or methylated BSA (mBSA) into the peritoneal cavity and by mBSA into the femur/tibial joint of immunized mice. This effect was associated with decreased leukocyte rolling, adhesion, and P-selectin and ICAM-1 expression on endothelium. Predictably, treatment of animals with the H(2)S donors, NaHS or Lawesson's reagent, enhanced these parameters. Moreover, the NaHS enhancement of neutrophil migration was not observed in ICAM-1-deficient mice. Neither PAG nor NaHS treatment changed LPS-induced CD18 expression on neutrophils, nor did the LPS- and mBSA-induced release of neutrophil chemoattractant mediators TNF-alpha, keratinocyte-derived chemokine, and LTB(4). Furthermore, in vitro MIP-2-induced neutrophil chemotaxis was inhibited by PAG and enhanced by NaHS treatments. Accordingly, MIP-2-induced CXCR2 internalization was enhanced by PAG and inhibited by NaHS treatments. Moreover, NaHS prevented MIP-2-induced CXCR2 desensitization. The PAG and NaHS effects correlated, respectively, with the enhancement and inhibition of MIP-2-induced G protein-coupled receptor kinase 2 expression. The effects of NaHS on neutrophil migration both in vivo and in vitro, together with CXCR2 internalization and G protein-coupled receptor kinase 2 expression were prevented by the ATP-sensitive potassium (K(ATP)(+)) channel blocker, glybenclamide. Conversely, diazoxide, a K(ATP)(+) channel opener, increased neutrophil migration in vivo. Together, our data suggest that during the inflammatory response, H(2)S augments neutrophil adhesion and locomotion, by a mechanism dependent on K(ATP)(+) channels.

  17. ST3Gal III modulates breast cancer cell adhesion and invasion by altering the expression of invasion-related molecules.

    PubMed

    Cui, Hong-Xia; Wang, Honglan; Wang, Yuchun; Song, Juan; Tian, Hua; Xia, Chunhui; Shen, Yetong

    2016-12-01

    Changes in the carbohydrate structure on the surface of tumor cells is an important feature of cancer metastasis. The specific role of sialic acids in the glycoconjugate terminal has not yet been clearly elucidated in these processes. Previously, we reported that α2,3-sialic acid residues in breast cancer are associated with metastatic potential. The α2,3-sialyltransferase ST3Gal III, which adds α2,3-sialic acids to glycoproteins, is overexpressed in various tumors, and enzyme activity is correlated with tumor metastasis, yet its mechanistic role has not been fully evaluated. In the present study, we aimed to investigate the influence of ST3Gal III on key steps in the process of breast cancer metastasis. ST3Gal III-overexpressing and ST3Gal III-silenced breast cancer MDA-MB-231 cell lines were generated. They showed an increase or decrease in the tumor-associated antigen sialyl-Lewis X (SLeX). The E-selectin binding capacity of the transfectants was proportional to cell surface SLeX levels. Cell migration and invasion were positively correlated with ST3Gal III levels. Moreover, ST3Gal III expression modulated the protein expression of invasion-related molecules, including β1 integrin, matrix metalloproteinase (MMP)-2, MMP-9 and cyclooxygenase-2, which may account for the mechanism involved in the effects of ST3Gal III on breast cancer invasiveness. In conclusion, our findings in these novel models of ST3Gal III expression revealed a critical requirement for